[8.x](backport #6563) github-actions(pre-commit): detect merge conflicts and shebangs

[mergify]

What does this PR do?

Use pre-commit with a subset of checks and run in the CI always.

Why is it important?

Similarly done at elastic/beats#42377

Help with detecting merge conflicts or shebang issues

Checklist

• I have read and understood the pull request guidelines of this project.
• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files
• I have added tests that prove my fix is effective or that my feature works
• I have added an entry in ./changelog/fragments using the changelog tool
• I have added an integration test or an E2E test

Disruptive User Impact

How to test this PR locally

Related issues

Questions to ask yourself

• How are we going to support this in production?
• How are we going to measure its adoption?
• How are we going to debug this?
• What are the metrics I should take care of?
• ...

---

This is an automatic backport of pull request #6563 done by [Mergify](https://mergify.com).

[elastic-sonarqube]

Quality Gate passed

Issues
0 New issues
0 Fixed issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
No data about Duplication

See analysis details on SonarQube

[mergify]

This pull request is now in conflicts. Could you fix it? 🙏
To fixup this pull request, you can check out it locally. See documentation: https://help.github.com/articles/checking-out-pull-requests-locally/

git fetch upstream
git checkout -b mergify/bp/8.x/pr-6563 upstream/mergify/bp/8.x/pr-6563
git merge upstream/8.x
git push upstream mergify/bp/8.x/pr-6563

[mergify]

This pull request has not been merged yet. Could you please review and merge it @v1v? 🙏

[mergify]

This pull request has not been merged yet. Could you please review and merge it @v1v? 🙏

[mergify]

This pull request has not been merged yet. Could you please review and merge it @v1v? 🙏