KStandardShortcut::findByName(name): use QAnyStringView arg type
((Build on top of !243 (merged), only last commit is this very MR))
Actually only a few users of findByName() currently by what lxr reports, but those have different string types.
Given internally nothing requires a certain string instance type, this seems a valid candidate for using QAnyStringView. Already spares runtime memalloc conversion in lib's own StandardShortcutWatcher.