Admins can easily switch maps via voting menu by accident

[shiftycats]

Describe the bug Depending on whether player is logged in as admin, clicking on a map in the voting menu can either switch maps or place a vote. This leads to admins accidentally changing maps if they forget to logout before voting.

To Reproduce

1. Login as admin.
2. Open the voting menu.
3. Click on any map.

Expected behavior

1. Admin right-clicks on the desired map and selects Switch to from the context menu.
2. A confirmation window is shown with Continue and Abort options (as an additional safeguard).