Properly export bytes from paramiko.py3compat (#6113)

stubs/paramiko/paramiko/py3compat.pyi

@@ -8,7 +8,6 @@ PY2: bool
 string_types: Type[Any] | Sequence[Type[Any]]
 text_type: Type[Any] | Sequence[Type[Any]]
 bytes_types: Type[Any] | Sequence[Type[Any]]
-bytes = bytes
 integer_types: Type[Any] | Sequence[Type[Any]]
 long = int
 
@@ -29,6 +28,8 @@ else:
     StringIO = cStringIO.StringIO
     BytesIO = StringIO
 
+bytes = builtins.bytes
+
 def byte_ord(c: int | str) -> int: ...
 def byte_chr(c: int) -> bytes: ...
 def byte_mask(c: int, mask: int) -> bytes: ...