gh-144446: Fix some frame object thread-safety issues (gh-144479)

Fix thread-safety issues when accessing frame attributes while another
thread is executing the frame:

- Add critical section to frame_repr() to prevent races when accessing
  the frame's code object and line number

- Add _Py_NO_SANITIZE_THREAD to PyUnstable_InterpreterFrame_GetLasti()
  to allow intentional racy reads of instr_ptr.

- Fix take_ownership() to not write to the original frame's f_executable