KDE: Update KDE Plasma Desktop 6 to 6.0.4

KDE Plasma 6.0.4, Bugfix Release for April

Tuesday, 16 April 2024. Today KDE releases a bugfix update to KDE Plasma
6, versioned 6.0.4.

This release adds three weeks' worth of new translations and fixes from
KDE's contributors. The bugfixes are typically small but important and
include:

 * Foldermodel: Export urls to the Desktop Portal on drag and copy.
 * System Monitor: Fix the column configuration dialog being too small
   on the overview page.
 * Applets/battery: Check actual battery for charge state workaround.

View full changelog:	https://kde.org/announcements/changelogs/plasma/6/6.0.3-6.0.4

(cherry picked from commit d884176a)