gs-updates-section: Drop suggested-action from cancel button

It doesn’t fit well with the `install-progress` styling, and we don’t
particularly want to suggest that the user cancels their in-progress
updates anyway.

Signed-off-by: Philip Withnall <pwithnall@endlessos.org>

Fixes: #1396
3 jobs for 1396-update-cancel-button-styling in 4 minutes and 34 seconds (queued for 2 seconds)