`test_xpickle` isn't running (failing) anywhere

[StanFromIreland]

This resulted in #144878 and, the following day, #144927.

The test requires the 'xpickle' resource (and for various Python versions to be installed) but it is not included in ALL_RESOURCES, so currently it is not run on any buildbot:

cpython/Lib/test/libregrtest/utils.py

Line 44 in 34913b1

RESOURCE_NAMES = ALL_RESOURCES + ('extralargefile', 'tzdata', 'xpickle', 'wantobjects')

Some options:

1. Adding the resource to all. @serhiy-storchaka there is no comment above explaining why it was excluded, did it cause issues?
2. Run it in the CI, this would be best done as a separate job, since it requires several installed python versions.
3. Run it on a buildbot.

[serhiy-storchaka]

This was for purpose. Resources like "extralargefile" and "xpickle" are not included in "all" because these tests require a lot of resources. They are purposed to be used in manual testing -- it is not to waste resources on them every day, but you should be able to run them if you need.