During the migration the automated script to update the copyright
headers accidentally got rid of some of the existing copyright lines.
Reinstate them.
* Add type hints to `tests/rest/client`
* newsfile
* fix imports
* add `test_account.py`
* Remove one type hint in `test_report_event.py`
* change `on_create_room` to `async`
* update new functions in `test_third_party_rules.py`
* Add `test_filter.py`
* add `test_rooms.py`
* change to `assertEquals` to `assertEqual`
* lint