Add new KCM: kde-config-updates.

Added new KCM module based on changes in @plasma/discover/09db9dd3

Should resolve:

01:51:32 dh_missing --fail-missing
01:51:32 Overlay Executing ["dh_missing", "--fail-missing"]
01:51:32 dh_missing: warning: usr/lib/x86_64-linux-gnu/qt5/plugins/kcms/kcm_updates.so exists in debian/tmp but is not installed to anywhere
01:51:32 dh_missing: warning: usr/share/kpackage/kcms/kcm_updates/metadata.json exists in debian/tmp but is not installed to anywhere
01:51:32 dh_missing: warning: usr/share/kpackage/kcms/kcm_updates/metadata.desktop exists in debian/tmp but is not installed to anywhere
01:51:32 dh_missing: warning: usr/share/kpackage/kcms/kcm_updates/contents/ui/main.qml exists in debian/tmp but is not installed to anywhere
01:51:32 dh_missing: warning: usr/share/kservices5/kcm_updates.desktop exists in debian/tmp but is not installed to anywhere
01:51:32 dh_missing: error: missing files, aborting