Add Patrick Bajao as workhorse maintainer

Why is this change being made?

Hi GitLab Workhorse maintainers!

I'd like to propose to add me as a maintainer of gitlab-workhorse project.

I've been a traintainer for about 1 year and 7 months and was involved in reviewing a number of gitlab-workhorse recently related to different features. It's been a while since workhorse didn't get that much activity until 7 months ago. That helped me be familiar and comfortable with the project. I believe I'm ready to be a maintainer now.

During that span, I opened 9 MRs that were merged (complexity varies, not a lot as our group didn't need to touch workhorse that much). Was also able to review 33 MRs as a traintainer. These helped me be familiar with the codebase and its features (though not everything) and improved my Go skills.

Author Checklist

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