Update mheap/github-action-required-labels action to v4

[juul-mobile-bot]

This PR contains the following updates:

Package	Type	Update	Change
mheap/github-action-required-labels	action	major	v3 -> v4

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⚠ Dependency Lookup Warnings ⚠

Warnings were logged while processing this repo. Please check the logs for more information.

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Release Notes

mheap/github-action-required-labels

### [`v4`](https://togithub.com/mheap/github-action-required-labels/releases/tag/v4) [Compare Source](https://togithub.com/mheap/github-action-required-labels/compare/v3...v4) Tag that always points to the latest commit in the v4.x.x series of releases

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Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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• [ ] If you want to rebase/retry this PR, check this box

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This PR has been generated by Renovate Bot.

[github-actions[bot]]

Test Results

  5 files  ±0    5 suites  ±0   31s :stopwatch: -4s 17 tests ±0  17 :heavy_check_mark: ±0  0 :zzz: ±0  0 :x: ±0  19 runs  ±0  19 :heavy_check_mark: ±0  0 :zzz: ±0  0 :x: ±0 

Results for commit 058dc9b4. ± Comparison against base commit 6327d732.

:recycle: This comment has been updated with latest results.