integration tests minor improvements

[slimreaper35]

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[eskultety]

This gets the job done although I wonder if we could improve things a little by enclosing it in a variable called extra to make it more explicit that this is an unusual case.

Ultimately we might need to rename SUPPORTED_PMS to something else if the solution will need to consider other data beyond the PM scope (currently such changes run all integration tests), but that is out of scope for this PR.

[slimreaper35]

Do you mean something like this ?

SUPPORTED_PMS = list(resolver._package_managers)
DEV_PMS = list(resolver._dev_package_managers)
EXTRA_PMS = ["yarn_classic"]

ALL_PMS: frozenset[str] = frozenset(SUPPORTED_PMS + DEV_PMS + EXTRA_PMS)

[eskultety]

Pretty much, except that ALL_PMS would be named something else, e.g. TRACKED_DIRS or something more descriptive once you leave the realm of only wanting to filter tests solely based on actual pkg mgr backends. Like I said, we don't need to do that part now since we only have a single representative for the "extra" part so that would suffice :) .