Make MR Widget Collapsible/Smaller/Less Content when **WIP**

Currently when a MR is WIP there is a bunch of information that really doesn't matter.

Things that matter

1. Pipeline Stages/Statues
2. Branch name
3. Target branch

Otherwise

Maybe collapsible is a bad word for this, but the widget should be of reduced scope until we need it's full power.

Something like this would be just fine, and reduces the amount of noise the widget creates.

/cc @tauriedavis @dimitrieh