Co-authored-by: Patrick Cloke <clokep@users.noreply.github.com>

* Two scripts are basically entry_points already
* Move and rename scripts/* to synapse/_scripts/*.py
* Delete sync_room_to_group.pl
* Expose entry points in setup.py
* Update linter script and config
* Fixup scripts & docs mentioning scripts that moved

Co-authored-by: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com>

Use $(...) notation instead of legacy backticked `...`.

https://github.com/koalaman/shellcheck/wiki/SC2006



Signed-off-by: Dan Callahan <danc@element.io>

Double quote to prevent globbing and word splitting.

https://github.com/koalaman/shellcheck/wiki/SC2086



Signed-off-by: Dan Callahan <danc@element.io>

Quote this to prevent word splitting

https://www.shellcheck.net/wiki/SC2046



Signed-off-by: Dan Callahan <danc@element.io>

Fix broken export-data admin command and add a test for it to CI