Make the garbage collection alert non-dismissible

[gtsiolis]

Problem

We receive quite a few requests to restore deleted workspaces due to Garbage Collection which automatically deletes unused workspaces after 14 days of inactivity.

See also relevant issues in #2531.

Proposal

After having a short discussion with @jankeromnes and @ArthurSens, a smaller and quicker change that could benefit users here would be to make the existing garbage collection alert non-dismissible and remove the Dismiss button as described in the proposal in #2531.

Allow the product to have a non-dismissable message on the top of the list about garbage collection.

Benefits

This will bring back the garbage collection alert for users that have previously dismissed this message.

Risks

This will bring back the garbage collection alert for users that have previously dismissed this message.

[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 an issue. Will be resolved in #3300.

[gtsiolis]

Resolved with the dashboard redesign. ✔️