Previously, Tools/scripts/run_tests.py was used to add Python options to the command line:-u -E -W default -bb. But regrtest is now able to do it when--fast-ci and--slow-ci options are used.

I propose moving the remaining code of Tools/scripts/run_tests.py for cross compilation and HOSTRUNNER directly in libregrtest.

Linked PRs

• gh-110152: regrtest handles cross compilation and HOSTRUNNER #110156