Add a confirmation modal when leaving a team or removing team members

[gtsiolis]

Problem to solve

When you leave a team or remove a team member there's no confirmation for this destructive action.

Proposal

We could use a confirmation modal as done with other destructive actions like deleting an Environment Variable, etc.

See also #4623.

[gtsiolis]

This looks like a good issue for Engineering Groundwork, right? Cc @jankeromnes @AlexTugarev @svenefftinge

See also #4408.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[gtsiolis]

Still relevant.