Add type hints to `synapse/storage/databases/main/events_worker.py` (#11411)

changelog.d/11411.misc

mypy.ini

synapse/replication/slave/storage/_slaved_id_tracker.py

synapse/replication/slave/storage/push_rule.py

synapse/replication/tcp/streams/events.py

synapse/state/__init__.py

synapse/state/v1.py

synapse/storage/_base.py

synapse/storage/databases/main/events.py

synapse/storage/databases/main/events_worker.py

synapse/storage/databases/main/push_rule.py

synapse/storage/util/id_generators.py

tests/replication/test_sharded_event_persister.py