Bumps [mypy](https://github.com/python/mypy) from 1.10.1 to 1.11.2.
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/python/mypy/blob/master/CHANGELOG.md">mypy's
changelog</a>.</em></p>
<blockquote>
<h3>Mypy 1.11.2</h3>
<ul>
<li>Alternative fix for a union-like literal string (Ivan Levkivskyi, PR
<a
href="https://redirect.github.com/python/mypy/pull/17639">17639</a>)</li>
<li>Unwrap <code>TypedDict</code> item types before storing (Ivan
Levkivskyi, PR <a
href="https://redirect.github.com/python/mypy/pull/17640">17640</a>)</li>
</ul>
<h3>Acknowledgements</h3>
<p>Thanks to all mypy contributors who contributed to this release:</p>
<ul>
<li>Alex Waygood</li>
<li>Alexander Leopold Shon</li>
<li>Ali Hamdan</li>
<li>Anders Kaseorg</li>
<li>Ben Brown</li>
<li>Bénédikt Tran</li>
<li>bzoracler</li>
<li>Christoph Tyralla</li>
<li>Christopher Barber</li>
<li>dexterkennedy</li>
<li>gilesgc</li>
<li>GiorgosPapoutsakis</li>
<li>Ivan Levkivskyi</li>
<li>Jelle Zijlstra</li>
<li>Jukka Lehtosalo</li>
<li>Marc Mueller</li>
<li>Matthieu Devlin</li>
<li>Michael R. Crusoe</li>
<li>Nikita Sobolev</li>
<li>Seo Sanghyeon</li>
<li>Shantanu</li>
<li>sobolevn</li>
<li>Steven Troxler</li>
<li>Tadeu Manoel</li>
<li>Tamir Duberstein</li>
<li>Tushar Sadhwani</li>
<li>urnest</li>
<li>Valentin Stanciu</li>
</ul>
<p>I’d also like to thank my employer, Dropbox, for supporting mypy
development.</p>
<h2>Mypy 1.10</h2>
<p>We’ve just uploaded mypy 1.10 to the Python Package Index (<a
href="https://pypi.org/project/mypy/">PyPI</a>). Mypy is a static type
checker for Python. This release includes new features, performance
improvements and bug fixes. You can install it as follows:</p>
<pre><code>python3 -m pip install -U mypy
</code></pre>
<p>You can read the full documentation for this release on <a
href="http://mypy.readthedocs.io">Read the Docs</a>.</p>
<h3>Support TypeIs (PEP 742)</h3>
<p>Mypy now supports <code>TypeIs</code> (<a
href="https://peps.python.org/pep-0742/">PEP 742</a>), which allows</p>
<!-- raw HTML omitted -->
</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/python/mypy/commit/789f02c83a5d5cb35f5e33ba91df46c8fea6b28e"><code>789f02c</code></a>
Bump version to 1.11.2</li>
<li><a
href="https://github.com/python/mypy/commit/917cc75fd6f1417edb45eb77e449934f794c18fc"><code>917cc75</code></a>
An alternative fix for a union-like literal string (<a
href="https://redirect.github.com/python/mypy/issues/17639">#17639</a>)</li>
<li><a
href="https://github.com/python/mypy/commit/7d805b364ee80396e0b9ca906f32f901b2ac7e12"><code>7d805b3</code></a>
Unwrap TypedDict item types before storing (<a
href="https://redirect.github.com/python/mypy/issues/17640">#17640</a>)</li>
<li><a
href="https://github.com/python/mypy/commit/32675dddfacccef616557916cb872757605ab493"><code>32675dd</code></a>
Revert &quot;Fix Literal strings containing pipe characters&quot; (<a
href="https://redirect.github.com/python/mypy/issues/17638">#17638</a>)</li>
<li><a
href="https://github.com/python/mypy/commit/778542b93a6f5b3c168a8acc03717700ae6f8048"><code>778542b</code></a>
Revert &quot;Fix <code>RawExpressionType.accept</code> crash with
<code>--cache-fine-grained</code>&quot; (<a
href="https://redirect.github.com/python/mypy/issues/1">#1</a>...</li>
<li><a
href="https://github.com/python/mypy/commit/14ab742dec6b58a4e94772115cb3b5c67a4b3d33"><code>14ab742</code></a>
Bump version to 1.11.2+dev</li>
<li><a
href="https://github.com/python/mypy/commit/570b90a7a368f04c64f60af339d0ac1808c49c15"><code>570b90a</code></a>
Bump version to 1.11</li>
<li><a
href="https://github.com/python/mypy/commit/b3a102ef31f63a8a8ba32c8dbe160ddef3c43054"><code>b3a102e</code></a>
Fix <code>RawExpressionType.accept</code> crash with
<code>--cache-fine-grained</code> (<a
href="https://redirect.github.com/python/mypy/issues/17588">#17588</a>)</li>
<li><a
href="https://github.com/python/mypy/commit/aec04c74488d46a81a95ed3553b8e953a6ec59a7"><code>aec04c7</code></a>
Fix PEP 604 isinstance caching (<a
href="https://redirect.github.com/python/mypy/issues/17563">#17563</a>)</li>
<li><a
href="https://github.com/python/mypy/commit/cb44e4d8f18b9bc874f1076b33eec7ad67de165c"><code>cb44e4d</code></a>
Fix <code>typing.TypeAliasType</code> being undefined on python &lt;
3.12 (<a
href="https://redirect.github.com/python/mypy/issues/17558">#17558</a>)</li>
<li>Additional commits viewable in <a
href="https://github.com/python/mypy/compare/v1.10.1...v1.11.2">compare
view</a></li>
</ul>
</details>
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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

This is so that we can cache it.

We also move the sliding sync types to
`synapse/types/handlers/sliding_sync.py`. This is mainly in-prep for

The only change in behaviour is that
`RoomSyncConfig.combine_sync_config(..)` now returns a new room sync
config rather than mutating in-place.

Reviewable commit-by-commit.

---------

Co-authored-by: Eric Eastwood <eric.eastwood@beta.gouv.fr>

This is so that we can cache it.

We also move the sliding sync types to
`synapse/types/handlers/sliding_sync.py`. This is mainly in-prep for
#17599 to avoid circular imports.

The only change in behaviour is that
`RoomSyncConfig.combine_sync_config(..)` now returns a new room sync
config rather than mutating in-place.

Reviewable commit-by-commit.

---------

Co-authored-by: Eric Eastwood <eric.eastwood@beta.gouv.fr>

During the migration the automated script to update the copyright
headers accidentally got rid of some of the existing copyright lines.
Reinstate them.

Co-authored-by: David Robertson <davidr@element.io>
Co-authored-by: Patrick Cloke <patrickc@matrix.org>
Co-authored-by: Erik Johnston <erik@matrix.org>

Assert that the return type of callables wrapped in @cached
and @cachedList are cachable (aka immutable). 

Enable additional checks & clean-up unneeded configuration.

The cached decorators always return a Deferred, which was not
properly propagated. It was close enough when wrapping coroutines,
but failed if a bare function was wrapped.

Signed-off-by: Mathieu Velten <mathieuv@matrix.org>

Not enforced in config yet. One day.

Part of #9744

Removes all redundant `# -*- coding: utf-8 -*-` lines from files, as python 3 automatically reads source code as utf-8 now.

`Signed-off-by: Jonathan de Jong <jonathan@automatia.nl&gt;`>

 - Update black version to the latest
 - Run black auto formatting over the codebase
    - Run autoformatting according to [`docs/code_style.md
`](https://github.com/matrix-org/synapse/blob/80d6dc9783aa80886a133756028984dbf8920168/docs/code_style.md)
 - Update `code_style.md` docs around installing black to use the correct version

Cached functions accept an `on_invalidate` function, which we failed to add to the type signature. It's rarely used in the files that we have typed, which is why we haven't noticed it before.

This requires adding a mypy plugin to fiddle with the type signatures a bit.