4e35ca8e26
When a windowPreview is hovered or selected, it will show its window's title as a caption. That title may contain Newline characters which will effect the windowPreview size. Make the caption's St.Label use single line mode to prevent that. Fixes https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/4162 Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1822>