CI run against Twisted trunk is failing

[github-actions]

See https://github.com/matrix-org/synapse/actions/runs/2500711697

[DMRobertson]

tests/state/test_v2.py:512: error: Argument 1 to "ensureDeferred" has incompatible type "Coroutine[Any, Any, Mapping[Tuple[str, str], str]]"; expected "Union[Coroutine[Deferred[Dict[Tuple[str, str], str]], Any, Dict[Tuple[str, str], str]], Generator[Deferred[Dict[Tuple[str, str], str]], Any, Dict[Tuple[str, str], str]], Deferred[Dict[Tuple[str, str], str]]]"  [arg-type]
tests/handlers/test_federation.py:122: error: Need type annotation for "sg"  [var-annotated]
tests/handlers/test_federation.py:123: error: Argument 1 to "successResultOf" of "_Assertions" has incompatible type "Coroutine[Any, Any, Optional[int]]"; expected "Deferred[<nothing>]"  [arg-type]
tests/handlers/test_federation.py:152: error: Need type annotation for "sg2"  [var-annotated]
tests/handlers/test_federation.py:152: error: Argument 1 to "successResultOf" of "_Assertions" has incompatible type "Coroutine[Any, Any, Optional[int]]"; expected "Deferred[<nothing>]"  [arg-type]
tests/handlers/test_federation.py:175: error: Need type annotation for "sg"  [var-annotated]
tests/handlers/test_federation.py:176: error: Argument 1 to "successResultOf" of "_Assertions" has incompatible type "Coroutine[Any, Any, Optional[int]]"; expected "Deferred[<nothing>]"  [arg-type]
tests/handlers/test_federation.py:206: error: Need type annotation for "sg2"  [var-annotated]
tests/handlers/test_federation.py:206: error: Argument 1 to "successResultOf" of "_Assertions" has incompatible type "Coroutine[Any, Any, Optional[int]]"; expected "Deferred[<nothing>]"  [arg-type]

Would guess Twisted changed type annotations recently. twisted/twisted#1736 Probably?