mergify: fix needs work labels if CI fails

[0xc0170]

Summary of changes

We have a clash with needs work and needs CI labels. If CI fails, we need to be in CI stage. Check for needs: CI label and apply work only if it was CI.

Otherwise we would be in the loop (we had couple of PRs with 400 messages from mergify). Because we did not check for previous stage (like this fix is doing), we had PRs where both states were true (apply needs work and apply needs CI labels - remove any other label). If we are more strict, and apply needs work only if CI fails and it is in CI stage, we should avoid having this infinite loops.

Impact of changes

Migration actions required

Documentation

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Pull request type

[x] Patch update (Bug fix / Target update / Docs update / Test update / Refactor)
[] Feature update (New feature / Functionality change / New API)
[] Major update (Breaking change E.g. Return code change / API behaviour change)

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Test results

[x] No Tests required for this change (E.g docs only update)
[] Covered by existing mbed-os tests (Greentea or Unittest)
[] Tests / results supplied as part of this PR

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Reviewers

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[ciarmcom]

@0xc0170, thank you for your changes.
@ARMmbed/mbed-os-maintainers please review.

[adbridge]

Why has the remove bit changed? If there is a needs:review doesn't that also need removing ?

[0xc0170]

This stage is from CI to needs work, we should not touch review label as it was already removed in a stage before (review -> CI).

[0xc0170]

Line 62 should be more important for this fix. I removed review part of this fix as it does not make sense to be removed, or does it.

[adbridge]

Same here ?

[0xc0170]

Same is above, these 2 stages here are for CI failures, nothing related to review.

i also added needs: CI needs to be already part of the PR.

[0xc0170]

Ci started