Added tooltips to Dashboard Activities-Overview filter options

What does this MR do?

Adds tooltips to the dahboard Activities-Overview filter options

How confident are you it won't break things if deployed?

very

Links to related issues

None

How to test

Checkout, hover over filter options on dashboard. No automated test needed (?)

Screenshots (if applicable)

Checklist

• added a test, or explain why one is not needed/possible...
• no unrelated changes
• asked someone for a code review
• joined #foodsharing-beta channel at https://slackin.yunity.org
• added an entry to CHANGELOG.md (description, merge request link, username(s))
• Once your MR has been merged, you are responsible to update the #foodsharing-beta Slack channel about what has been changed here. They will test your work in different browsers, roles or other settings