Add third_party module callbacks to check if a user can delete a room and deactivate a user (#12028)

* Add check_can_deactivate_user

* Add check_can_shutdown_rooms

* Documentation

* callbacks, not functions

* Various suggested tweaks

* Add tests for test_check_can_shutdown_room and test_check_can_deactivate_user

* Update check_can_deactivate_user to not take a Requester

* Fix check_can_shutdown_room docs

* Renegade and use `by_admin` instead of `admin_user_id`

* fix lint

* Update docs/modules/third_party_rules_callbacks.md

Co-authored-by: Brendan Abolivier <babolivier@matrix.org>

* Update docs/modules/third_party_rules_callbacks.md

Co-authored-by: Brendan Abolivier <babolivier@matrix.org>

* Update docs/modules/third_party_rules_callbacks.md

Co-authored-by: Brendan Abolivier <babolivier@matrix.org>

* Update docs/modules/third_party_rules_callbacks.md

Co-authored-by: Brendan Abolivier <babolivier@matrix.org>

Co-authored-by: Brendan Abolivier <babolivier@matrix.org>