allow multiple group sessions on a single dashboard

[JonJagger]

Often in a large group you want to create 3 group practice sessions (say)
which all have the same exercise (FizzBuzz) but in a selection of language/test-frameworks.
The idea is that in the creator (Gitlab) repo when you setup a group practice you will
be able to select (checkboxes?) several (say up to 5) language/test-frameworks

Somehow these IDs will all be linked together.

The dashboard UX will need to be updated.

• the name of the (currently one) language/test-framework at the top will disappear
• there will be a tab (or dropdown?) for each language/test-framework
• when auto refresh is on, every minute (say) rotate to the next tab