[Identity] Update async __aexit__ typing (Azure#31830)

This ensures the signature of __aexit__ matches that the signature of
the __aexit__ in the AsyncTokenCredential protocol.

Signed-off-by: Paul Van Eck <paulvaneck@microsoft.com>

sdk/identity/azure-identity/CHANGELOG.md

@@ -12,6 +12,8 @@
 
 ### Other Changes
 
+- Update typing of async credentials to match the `AsyncTokenCredential` protocol.
+
 ## 1.14.0 (2023-08-08)
 
 ### Features Added

sdk/identity/azure-identity/azure/identity/aio/_internal/__init__.py

@@ -3,6 +3,8 @@
 # Licensed under the MIT License.
 # ------------------------------------
 import abc
+from types import TracebackType
+from typing import Optional, Type
 
 from .aad_client import AadClient
 from .decorators import wrap_exceptions
@@ -16,7 +18,12 @@ async def close(self):
     async def __aenter__(self):
         return self
 
-    async def __aexit__(self, *args):
+    async def __aexit__(
+        self,
+        exc_type: Optional[Type[BaseException]] = None,
+        exc_value: Optional[BaseException] = None,
+        traceback: Optional[TracebackType] = None,
+    ) -> None:
         await self.close()