tarfile: improve bytes handling (#9076)

stdlib/tarfile.pyi

@@ -346,7 +346,7 @@ class TarInfo:
     pax_headers: Mapping[str, str]
     def __init__(self, name: str = ...) -> None: ...
     @classmethod
-    def frombuf(cls: Type[Self], buf: bytes, encoding: str, errors: str) -> Self: ...
+    def frombuf(cls: Type[Self], buf: bytes | bytearray, encoding: str, errors: str) -> Self: ...
     @classmethod
     def fromtarfile(cls: Type[Self], tarfile: TarFile) -> Self: ...
     @property