workspace: don't rearrange immediately when a window with struts gets removed
Otherwise, rearrange can happen on intermediate output configurations, as layer shell windows can get closed in response to outputs being disabled. That rearrange on intermediate output configurations can confuse the placement tracker logic, which may then move windows to weird locations or even offscreen
(cherry picked from commit 24ab95bd)
Co-authored-by: Xaver Hugl xaver.hugl@gmail.com