wayland: Update cursor surface scale when output scale changes

Cursor surfaces didn't listen for output scale changes, meaning they
didn't adapt their scale when an output changed scale, which could
happen for example when changing the monitor scale via Settings.
1 job for <span class="ref-name">wip/cursor-output-scale-changes-3-24</span> in 8 minutes and 18 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
passed #54647
build

00:08:18