Move flaky tests to a separate workflow on CI

[jtpio]

References

The long term motivation is to be able to reach a full green CI some time soon.

For now, this change moves some of the known flaky tests to their own workflow, so they can easily be restarted without re-running everything else. The current list includes:

• js-services
• js-apputils

Code changes

CI

User-facing changes

None

Backwards-incompatible changes

None

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[jtpio]

The js-services tests also seem to be timing out locally, so hopefully it should be possible to fix them.

[jtpio]

The js-services tests also seem to be timing out locally, so hopefully it should be possible to fix them.

This seems to be reproducible locally when running the ikernel.spec.ts tests:

jlpm run test test/kernel/ikernel.spec.ts 

[jtpio]

It looks like js-services tests might have started timing out in #9484

While they were still passing in the previous PR #9483

Locally, some hints that it might be related to timeouts on kernel restarts:

[jtpio]

Testing without ikernel.spec.ts locally seems to pass:

It looks like the issue is with the restart and shutdown logic.

[jtpio]

Looks like the services tests are fixed by #9806.

Rebasing to only keep js-apputils in the flaky group for now.

[blink1073]

Thanks!