gh-138313: Suppress ResourceWarnings and restore skipped test

[jaraco]

Replaces the previous workaround (skip) with a less janky yet still janky workaround. See the log in the issue for details.

• Issue: ResourceWarnings in test_importlib in select buildbots #138313

Closes #138313

[bedevere-bot]

🤖 New build scheduled with the buildbot fleet by @jaraco for commit 43357c2 🤖

Results will be shown at:

https://buildbot.python.org/all/#/grid?branch=refs%2Fpull%2F138597%2Fmerge

If you want to schedule another build, you need to add the 🔨 test-with-buildbots label again.

[bedevere-bot]

🤖 New build scheduled with the buildbot fleet by @jaraco for commit e8eb0d0 🤖

Results will be shown at:

https://buildbot.python.org/all/#/grid?branch=refs%2Fpull%2F138597%2Fmerge

If you want to schedule another build, you need to add the 🔨 test-with-buildbots label again.

[bedevere-bot]

🤖 New build scheduled with the buildbot fleet by @jaraco for commit c9f5305 🤖

Results will be shown at:

https://buildbot.python.org/all/#/grid?branch=refs%2Fpull%2F138597%2Fmerge

If you want to schedule another build, you need to add the 🔨 test-with-buildbots label again.

[jaraco]

There are failures in BSD with the error "invalid line type". I assume those are ignorable.

[bedevere-bot]

🤖 New build scheduled with the buildbot fleet by @jaraco for commit c1b4676 🤖

Results will be shown at:

https://buildbot.python.org/all/#/grid?branch=refs%2Fpull%2F138597%2Fmerge

If you want to schedule another build, you need to add the 🔨 test-with-buildbots label again.

[jaraco]

I can see the refleaks PR builders are failing in test_capi since 3 days ago, so unrelated to these changes. I'm going to proceed with this change. I welcome others to come in and find an even more robust solution.