Update mergify to prevent incorrectly firing rule to update ready-for-review label

[jimmygchen]

Unfortunately I think the mergify rules need to be updated again.

With the current rule, it's not possible to mark a PR with passing CI as waiting-on-author. Mergify will immediately remove this label and mark it as ready-for-review because of the following rule:

lighthouse/.github/mergify.yml

Lines 41 to 51 in 7759cb8

	- name: Update labels when PR is unblocked
	conditions:
	- -closed
	- -draft
	- label=waiting-on-author
	- -conflict
	# Unfortunately, it doesn't look like there's an easy way to check for PRs pending
	# CI workflows approvals.
	- check-success=test-suite-success
	- check-success=local-testnet-success
	- "#review-requested > 0"

I've now added an additional condition, so it won't fire if there's a change request or unresolved thread:

      - or:
         - "#changes-requested-reviews-by = 0"
         - "#review-threads-unresolved = 0"

I'm hoping this improves things, tested the conditions against the following PRs:

• Implement EIP-7892 BPO hardforks #7521: has unresolved threads, should not label ready-for-review
• Don't create child lookup if parent is faulty #7118: has requested change, should not label ready-for-review

If this condition proves to be painful without much benefit we can consider removing it, but I'm willing to give it another try.

I've also removed the comment section of this condition, i'm getting feedback that it adds unnecessary noise.

[mergify]

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