repositories: update qt overlay description

Signed-off-by: Davide Pesavento <[email protected]>

files/overlays/repositories.xml

@@ -3302,7 +3302,7 @@
  <repo quality="experimental" status="official">
  <name>qt</name>
  <description>Official testing overlay for Qt and related packages, provided
- by Gentoo's Qt team. Contains ebuilds for Qt4 and Qt5 prereleases and live ebuilds,
+ by Gentoo's Qt team. Contains ebuilds for Qt5 and Qt6 prereleases and live ebuilds,
  plus various (non-KDE) applications and utilities that use Qt.</description>
  <homepage>https://github.com/gentoo/qt</homepage>
  <owner type="project">