* More systematic gcc coverage, based on https://github.com/pybind/pybind11/pull/4074#issuecomment-1188385580

* Fix complete fail.

* Resolve GCC 11 & 12 "redundant move in return statement" warnings.

* Also add clang 11, 12, 13 (to gather info for warning suppressions).

* Add & use `PYBIND11_DETECTED_CLANG_WITH_MISLEADING_CALL_STD_MOVE_EXPLICITLY_WARNING`