Workspace: Better check of registered client shortcuts
Do not discard a shortcut immediately when it is already registered in KGlobalAccel, because there could be possible dangling shortcuts if they weren't properly cleaned-up (ex. after a crash).
Instead we delay the check for conflicts with other client shortcuts to the second loop, which we know is up to date.
Checked that it fixes the bug while testGlobalShortcuts
still passes.
BUG: 442215 FIXED-IN: 5.22.80