Convert simple_update* and simple_select* to async (#8173)

changelog.d/8173.misc

synapse/handlers/room.py

synapse/storage/database.py

synapse/storage/databases/main/__init__.py

synapse/storage/databases/main/directory.py

synapse/storage/databases/main/e2e_room_keys.py

synapse/storage/databases/main/event_federation.py

synapse/storage/databases/main/group_server.py

synapse/storage/databases/main/media_repository.py

synapse/storage/databases/main/profile.py

synapse/storage/databases/main/receipts.py

synapse/storage/databases/main/registration.py

synapse/storage/databases/main/room.py

synapse/storage/databases/main/user_directory.py

tests/handlers/test_stats.py

tests/storage/test_base.py

tests/storage/test_directory.py

tests/storage/test_main.py

tests/test_federation.py