Issue #22156: Fix "comparison between signed and unsigned integers" compiler
warnings in the Python/ subdirectory.
Issue #22156: Fix "comparison between signed and unsigned integers" compiler
warnings in the Objects/ subdirectory.

PyType_FromSpecWithBases() and PyType_FromSpec() now reject explicitly negative
slot identifiers.
Issue #22156: Fix some "comparison between signed and unsigned integers"
compiler warnings in the Modules/ subdirectory.