Limit --maxprocesses for scripts/ci/run-tests when in GitHub runners

[ashovlin]

Issue #, if available: N/A

Description of changes:

• Reduce parallelization for unit/functional tests in GItHub to avoid the Error: The operation was canceled. we've been seeing recently on the GitHub runners. The operation was canceled. actions/runner#2468 and other threads about it suggest it may be due to excessive resource consumption.
• Updated some actions pins while I was here to avoid Node deprecation warnings.

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[kdaily]

This is a good simple fix for the problem!

Not against this change, but since we have pytest-xdist available, we could also use the methods suggested by that package to set the definition of -n auto, like through the environment variable PYTEST_XDIST_AUTO_NUM_WORKERS:

https://pytest-xdist.readthedocs.io/en/stable/distribution.html#running-tests-across-multiple-cpus

I suggest this because when running tests locally I sometimes do the opposite and increase max processes manually. This could affect folks running the tests locally if we dropped the default --maxprocesses to allow the env variable to work, though.

[ashovlin]

PYTEST_XDIST_AUTO_NUM_WORKERS

In f7f227e, we now check if PYTEST_XDIST_AUTO_NUM_WORKERS is set first. If it is, we use that to set --maxprocesses to match the user's desired number. This will let users override our defaults without modifying the script.

[kdaily]

Left a comment, but since the proposed change has the same effect and our test suite is failing extremely often now, I'm fine to move forward.

[kdaily]

I was thinking that --max-processes would no longer be needed if PYTEST_XDIST_AUTO_NUM_WORKERS was set and the fallback is needed for backwards compatibility if its not set:

Suggested change

	if os.getenv('PYTEST_XDIST_AUTO_NUM_WORKERS'):
	# If the user set PYTEST_XDIST_AUTO_NUM_WORKERS,
	# use that to limit max processes
	max_processes = int(os.environ['PYTEST_XDIST_AUTO_NUM_WORKERS'])
	elif os.getenv('GITHUB_ACTIONS', 'false') == 'true':
	# Limiting parallelism in GitHub, to avoid the
	# 'Error: The operation was canceled.' issues in 2026
	max_processes=3
	else:
	max_processes=4
	test_args += f'--numprocesses=auto --dist=loadfile --maxprocesses={max_processes} '
	test_args += f'--numprocesses=auto --dist=loadfile '
	# If the user set PYTEST_XDIST_AUTO_NUM_WORKERS,
	# let pytest use that to limit max processes
	# Otherwise, fall back to 4 since that's what was
	# previously used in this script.
	if not os.getenv('PYTEST_XDIST_AUTO_NUM_WORKERS'):
	test_args += f'--maxprocesses=4 '

Then it would be specifically set to 3 in the GitHub Actions yaml configurations that run the test suites.

[ashovlin]

From discussion, planning to merge this for now since tests are really bad yesterday, we can keep tweaking if there are users setting PYTEST_XDIST_AUTO_NUM_WORKERS.