Merged requested to merge p3732/nautilus:wip/p3732/operation-cancel into main
Using the same icon as for closing windows and dialogs can lead to user confusion and thus accidental cancellation of operations.
This adds and uses a new icon, inspired by Builder's use of it to stop ongoing operations.
Fixes #985 (closed)
Note: I checked and could not find the icon to be available in the Adwaita icon set.