Change type.__dict__ to a proper attribute (#14951)

stdlib/@tests/stubtest_allowlists/common.txt

@@ -237,7 +237,6 @@ asyncio.locks.Condition.release
 builtins.memoryview.__contains__  # C type that implements __getitem__
 builtins.reveal_locals  # Builtins that type checkers pretends exist
 builtins.reveal_type  # Builtins that type checkers pretends exist
-builtins.type.__dict__  # read-only but not actually a property; stubtest thinks it's a mutable attribute.
 
 # The following CodecInfo properties are added in __new__
 codecs.CodecInfo.decode

stdlib/@tests/test_cases/builtins/check_type.py

@@ -0,0 +1,4 @@
+class Meta(type): ...
+
+
+call = Meta.__dict__["__call__"]