* tests: Don't run tests that often segfault
* tests: drop all cross module gil tests
* tests: try skipping all macOS Python 3.9 tests
* tests: drop macOS Python 3.9
* ci: harden chrono test, mark another macos 4.9 dev failure
This should help with a little of the flakiness seen with the timing test
* Update tests/test_chrono.py
* Can also fail
This is only necessary if `get_internals` is called for the first time in a given module when the running thread is in a GIL-released state.
Fixes#1364
This avoids GIL deadlocking when pybind11 tries to acquire the GIL in a thread that already acquired it using standard Python API (e.g. when running from a Python thread).
