CI fixes: gconf2 is not supported in current Ubuntu LTS, stick to the 22.04 runner for now.

Author: agraef

.github/workflows/makefile.yml

@@ -52,7 +52,7 @@ jobs:
 
   ubuntu-build:
 
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     env:
       DEBEMAIL: "Albert Graef <aggraef@gmail.com>"