Improve compatibility with "nogil" Python and 3.11

[colesbury]

This makes a number of changes to improve compatibility with the
"nogil" Python fork as well as the Python 3.11+.

• Fix _code_reduce for 3.11b0 and nogil Python

• Use instr.argval in _walk_global_ops. This avoids adding a special
  case for 3.11+ (and is useful for nogil Python). In 3.11+, the argval
  for LOAD_GLOBAL would need to be divided by two to access the correct
  name. The 'argval' field already stores the correct name.

• Set __builtins__ before constructing de-pickled functions. (Useful
  for nogil Python)

• Fix test_recursion_during_pickling in Python 3.11+. Objects now have
  a default __getstate__ method so __getattr__ was never called,
  but __getattribute__ would still be called.

[colesbury]

There's still a bug in Python 3.11b0 that prevents the tests from passing:

python/cpython#92932

But once that is fixed all the tests should pass. (I've run the tests locally with a patched version of 3.11b0).

Also, I've included both changes for "nogil" and CPython 3.11 because some of the changes overlapped. Let me know if you'd prefer me to split up the PRs.

[pcmoritz]

Thanks a lot for your work on nogil Python -- I'm a big fan of this work! Last time I tried it out, I was running into CloudPickle not working so it is really great to see you are fixing it!

[codecov]

Codecov Report

Merging #470 (bb3c31b) into master (2fc334d) will increase coverage by 8.13%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #470      +/-   ##
==========================================
+ Coverage   84.47%   92.60%   +8.13%     
==========================================
  Files           4        4              
  Lines         715      717       +2     
  Branches      157      158       +1     
==========================================
+ Hits          604      664      +60     
+ Misses         87       32      -55     
+ Partials       24       21       -3     

Impacted Files	Coverage Δ
cloudpickle/cloudpickle.py	88.59% <100.00%> (+0.59%)	⬆️
cloudpickle/cloudpickle_fast.py	96.93% <100.00%> (+16.25%)	⬆️
cloudpickle/compat.py	100.00% <0.00%> (+30.00%)	⬆️

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[ogrisel]

Since we now have a nogil-specific branch in the code, we might want to have a nogil CI in the build matrix. However this will require compiling nogil-CPython from source which adds significant CI config complexity...

I tested locally with my up-to-date nogil venv and all cloudpickle tests pass though.

[ogrisel]

The dask distributed failure is unrelated and will be fixed concurrently in #471.

[ogrisel]

@pierreglaser any opinion on the changes in this PR?

[ogrisel]

The failures observed on the dowstream distributed CI run are the same as those observed in the master branch (see for instance the last build in #471).

So +1 for merging this on my side. But before making a release I would like to better understand what's going on with distributed, irrespective of the changes in this PR.

[ogrisel]

I can reproduce the same 19 failures for distributed main against the released cloudpickle 2.0.0, so they are definitely not related to any recent change in cloudpickle.

Let me merge this and release 2.1.0.