Data races with frame objects

[colesbury]

Bug report

We've fixed most of the data races with Python frame objects in:

• data races in frame inspection and tracebacks #128421

But I think we missed a few places, such as:

• repr(frame) on an frame that is executing or in the process of getting cleared
• frame.f_lasti

Additionally, I'd like to add more free threading tests for frames.

Linked PRs

• gh-144446: Fix some frame object thread-safety issues #144479