[libgtkmusic] Comment invalid <category> in DOAP file to pass git pre-receive hook

[Andre Klapper <aklapper src gnome org>]

commit ba0f3c78a5d8399132efc8091ee37dcaa51d95de
Author: Andre Klapper <a9016009 gmx de>
Date:   Sun Dec 16 00:23:18 2018 +0100

    Comment invalid <category> in DOAP file to pass git pre-receive hook

 libgtkmusic.doap | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/libgtkmusic.doap b/libgtkmusic.doap
index 8ceb30a..fdee5cc 100644
--- a/libgtkmusic.doap
+++ b/libgtkmusic.doap
@@ -14,7 +14,7 @@
   <!--<download-page rdf:resource="http://download.gnome.org/sources/libgtkmusic/"; />-->
   <bug-database rdf:resource="https://gitlab.gnome.org/GNOME/libgtkmusic/issues/"; />
 
-  <category rdf:resource="http://api.gnome.org/doap-extensions#desktop"; />
+  <!-- <category rdf:resource="http://api.gnome.org/doap-extensions#desktop"; /> -->
 
   <maintainer>
     <foaf:Person>