feat: Add merge conflict labeler workflow

[Gauvino]

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Description

Before merging the PR you have to manually add the label merge conflict

Put a label merge conflict on PR with merge conflict and comment also to say to the maintainer that PR as merge conflict.

Would be simpler to review PR and also gain time cause when merge conflict is detected the maintainer can solve it so you don't have to say to him manually to solve the merge conflict.

Checklist

• My code follows the style guidelines of this project
• I ran ESLint and other linters for modified files
• I have performed a self-review of my own code and tested it
• I have commented my code, particularly in hard-to-understand areas (including JSDoc for methods)
• My changes generates no new warnings
• My code needed automated testing. I have added them (this is optional task)

[CommanderStorm]

I don't think this would add value for my workflow.

Merging PRs is not much of the work required unless there have been other competing PRs such as in the case in this example:

• Timeline-based incident system #1253

In the case where it is significant work, that would have to be done by the PR-author though for scalabiltiy... => That would need a comment anyway..

[Gauvino]

No problem then, if you don't think you need this, just wanted to help the project, because it would certainly make you gain time by not having to say everytime there is a conflict on a PR to solve it and also do some triage.