devel/kf5-kcmutils: add upstream bug fix

From [1]
Fix KPluginSelector KCMs missing their metadata on plugin
loading

For the KWin KCMs we need the full metadata, because we read the
plugin keyword.

Without the X-KDE-ConfigModule key, plugins used to create a
symlink in the kservices5 folder to their metadata, which then
goes through the
legacy code path we would read all the metadata.
This includes the plugin keyword.

When consumers would this key, but have an old KWin version
which used the KPluginSelector class and a kcmutils version
which reads X-KDE-ConfigModule, but does not include this
bugfix, the plugin keyword will be empty and thus the config
files can not be located.

This makes it hard to fix the loading on kcmutils < 5.91, but
keeping the code working with KWin < 5.24.

Note: ports in main are not affected by this issue, as only plasma
5.23.x in conjunction with KDE Frameworks >= 5.88 is affected.
Which is what the quarterly tree is currently shipping.

[1] https://invent.kde.org/frameworks/kcmutils/commit/c9c58de65c07c8a940cb4c9b91777450698f635c

Upstream PR: https://bugs.kde.org/show_bug.cgi?id=444378

(cherry picked from commit a3d334a7096f43ea8492a952825c6d20fdcf3cae)