Add/Update team table with skills and projects to Developer Evangelism handbook

Why is this change being made?

The long listing in the team focus area section is hard to read, and misses some details. I've tried to extract as many activities as possible. @gitlab-de Please review and/or add more table entries.

I was reviewing @abuango 's community workshop slides, and the team overview slide reminded me to create a handbook update. Next to the table addition, I have removed myself from Engineering stable counterpart, this never was a reality, and product is the only department.

If you don't have a personal website and/or speakers portfolio yet, think about creating one :-)

Author Checklist

• Provided a concise title for this Merge Request (MR)
• Added a description to this MR explaining the reasons for the proposed change, per say why, not just what
  • Copy/paste the Slack conversation to document it for later, or upload screenshots. Verify that no confidential data is added.
• Assign reviewers for this MR to the correct Directly Responsible Individual/s (DRI)
  • If the DRI for the page/s being updated isn’t immediately clear, then assign it to one of the people listed in the Maintained by section on the page being edited
  • If your manager does not have merge rights, please ask someone to merge it AFTER it has been approved by your manager in #mr-buddies
• If the changes affect team members, or warrant an announcement in another way, please consider posting an update in #whats-happening-at-gitlab linking to this MR
  • If this is a change that directly impacts the majority of global team members, it should be a candidate for #company-fyi. Please work with internal communications and check the handbook for examples.

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