CT jenkins, x2go,pihole: Fixes for Debian 13

jenkins: Added missing packages  &  Fixed broken curl for getting current version  of GoLang
pihole: will now run a Gravity update on first setup,  to avoid errors  in the webUI
Readme  fixes for: collabora, domoticz & docker

CT-Build/Debian.yaml

@@ -1321,6 +1321,8 @@ packages:
     - jenkins
     - gcc
     - libc-dev   
+    - libharfbuzz0b
+    - fontconfig
     action: install
     variants:
     - jenkins
@@ -1447,6 +1449,7 @@ packages:
 #X2go pkgs    
   - packages:
     - gnome-themes-extra
+    - tango-icon-theme
     - xfce4-session
     - xfce4-settings
     - xfce4-panel