Add the missing PR template

[ph]

Add missing PR template

[elasticmachine]

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• Start Time: 2022-03-23T21:18:19.786+0000

• Duration: 5 min 12 sec

🤖 GitHub comments

To re-run your PR in the CI, just comment with:

• /test : Re-trigger the build.

• /package : Generate the packages.

• run integration tests : Run the Elastic Agent Integration tests.

• run end-to-end tests : Generate the packages and run the E2E Tests.

• run elasticsearch-ci/docs : Re-trigger the docs validation. (use unformatted text in the comment!)