Add comment when update protected branch fails

[AndrewGable]

Details

Adds a comment when the deploy process fails for the mobile deployer to fix the error and merge the PR to continue the deploy process.

Fixed Issues

$ https://github.com/Expensify/Expensify/issues/185234

Tests

1. Force this workflow to fail via these steps: Add comment when update protected branch fails #6706 (review)

[roryabraham]

Technically I think we can force updateProtectedBranch to fail by:

1. With the deploy checklist locked, merge and CP a pull request with some change in a specific file.
2. Merge and CP another PR changing that same file.
3. This should cause a merge conflict on staging when you go to CP the second PR to staging, which would fail the updateProtectedBranch workflow.

[AndrewGable]

Updated! I'll test once merged, thank you for the help coming up with the test steps.

[roryabraham]

Code LGTM. I think I might've been wrong about the test steps though – even if we have a merge conflict, I think we'll just commit the <== HEAD diff stuff, and then theoretically the PR would be mergeable. So actually I'm not sure how we reproduce an unmergable PR 🤷

[AndrewGable]

@puneetlath did you want to review this one?

[puneetlath]

I don't have a lot of context or knowledge in this area, but I took a look and it seems to make sense. Thanks for giving me the opportunity!

[OSBotify]

✋ This PR was not deployed to staging yet because QA is ongoing. It will be automatically deployed to staging after the next production release.

[OSBotify]

🚀 Deployed to staging by @puneetlath in version: 1.1.20-3 🚀

platform	result
🤖 android 🤖	success ✅
🖥 desktop 🖥	success ✅
🍎 iOS 🍎	failure ❌
🕸 web 🕸	success ✅

[OSBotify]

🚀 Deployed to production by @Julesssss in version: 1.1.21-1 🚀

platform	result
🤖 android 🤖	failure ❌
🖥 desktop 🖥	success ✅
🍎 iOS 🍎	success ✅
🕸 web 🕸	success ✅