cc-panel-list: Wrap "No results found" label
This effectively backports !2024 (merged) without requiring a UI or string change. It sets the same properties on the "No results found" label as LibAdwaita does with the AdwStatusPage.
Fixes #2788 (closed)
See https://gitlab.gnome.org/GNOME/libadwaita/-/blob/main/src/adw-status-page.ui?ref_type=heads#L39-L41.