Summary:
Use a nice new colorful icon.

Master only since this icon is provided by a symlink created in Frameworks 5.56.

CCBUG: 386748

Test Plan:
Before: {F6592327, size=full}
After: {F6592328, size=full}

Reviewers: #vdg, ndavis

Reviewed By: #vdg, ndavis

Subscribers: plasma-devel

Tags: #plasma

Differential Revision: https://phabricator.kde.org/D18800