Use proper return types for __await__ methods in redis.asyncio.client (#10379)

Author: sobolevn

stubs/redis/redis/asyncio/client.pyi

@@ -1,5 +1,5 @@
 from _typeshed import Incomplete, Unused
-from collections.abc import AsyncIterator, Awaitable, Callable, Iterable, Mapping, MutableMapping, Sequence
+from collections.abc import AsyncIterator, Awaitable, Callable, Generator, Iterable, Mapping, MutableMapping, Sequence
 from datetime import datetime, timedelta
 from types import TracebackType
 from typing import Any, ClassVar, Generic, NoReturn, Protocol, overload
@@ -67,7 +67,7 @@ class Redis(AbstractRedis, RedisModuleCommands, AsyncCoreCommands[_StrType], Asy
         redis_connect_func: ConnectCallbackT | None = None,
         credential_provider: CredentialProvider | None = None,
     ) -> None: ...
-    def __await__(self): ...
+    def __await__(self) -> Generator[Any, None, Self]: ...
     async def initialize(self) -> Self: ...
     def set_response_callback(self, command: str, callback: ResponseCallbackT): ...
     def load_external_module(self, funcname, func) -> None: ...
@@ -200,7 +200,7 @@ class Pipeline(Redis[_StrType], Generic[_StrType]):
     async def __aexit__(
         self, exc_type: type[BaseException] | None, exc_value: BaseException | None, traceback: TracebackType | None
     ) -> None: ...
-    def __await__(self): ...
+    def __await__(self) -> Generator[Any, None, Self]: ...
     def __len__(self) -> int: ...
     def __bool__(self) -> bool: ...
     async def reset(self) -> None: ...  # type: ignore[override]