Add a location button to the leaflet map

Closes #638 (closed)

What does this MR do?

Adds vue2-leaflet-locatecontrol (https://github.com/domoritz/leaflet-locatecontrol) to the main map. It adds a button that allows you to move the map to your current location.

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

quite sure, should work

Links to related issues

How to test

1. Checkout branch locally
2. Install the vue2-leaflet-locatecontrol package in the frontend as described in https://devdocs.foodsharing.network/docs/current/frontend/update-dependencies
3. Look at the map and try to use the button

Screenshots (if applicable)

Checklist

• added a test, or explain why one is not needed/possible...
• no unrelated changes
• asked someone for a code review
• set a "for:" label to indicate who will be affected by this change
• set the "API change" label if changes in the API are not backward compatible
• added to the next milestone (see https://gitlab.com/foodsharing-dev/foodsharing/-/milestones, unless it has a "for:Dev" label)
• added an entry to CHANGELOG.md
• added a short text in the release notes to /release-notes/YYYY-MM.md
• Once your MR has been merged, you are responsible to create a testing issue in the Beta Testing forum: https://foodsharing.de/region?bid=734&sub=forum. Please change the MRs label to "state:Beta testing".
  • Consider writing a detailed description in German.
  • Describe in a few sentences, what should be tested from a user perspective.
  • Also mention different settings (e.g. different browsers, roles, ...) how this change can be tested.
  • Be aware, that also non technical people should understand.

Closes #638 (closed)