This is an ongoing series of commits that are reformatting our Python
code. Reformatting is done with `black` (23.1.0).
If you end up having problems merging this commit because you have made
changes to a python file, the best way to handle that is to run `git
checkout --ours <yourfile>` and then reformat it with black.
RFC: https://discourse.llvm.org/t/rfc-document-and-standardize-python-code-style
Differential revision: https://reviews.llvm.org/D151460
Step over thread plans were claiming to explain the fork stop reasons,
which prevented the default fork logic (detaching from the child
process) from kicking in. This patch changes that.
Differential Revision: https://reviews.llvm.org/D141605
