Add empty state when all activity is filtered out of MR view

Everyone can contribute. Help move this issue forward while earning points, leveling up and collecting rewards.

• Work on this issue
• Close this issue

Issue

If you de-select all activity options, the Activity section is empty

Proposal

Add empty state when all options are deselected

Illustration: https://gitlab-org.gitlab.io/gitlab-svgs/illustrations?q=illustrations%2Fempty-state%2Fempty-activity-md.svg

Text:

No merge request activity to display

To see activity and comments for this merge request, select at least one activity filter.