kdePackages.khelpcenter: runtime dependency on kio-extras (through wrapQtAppsHook) to retrieve manpages

pkgs/kde/gear/khelpcenter/default.nix

···
   xapian,
   man-db,
   python3,
+  kio-extras,
 }:
 mkKdeDerivation {
   pname = "khelpcenter";
···
     qtwebengine
     xapian
     python3
+    kio-extras
   ];
   patches = [
     (replaceVars ./use_nix_paths_for_mansearch_utilities.patch {