[damned-lies] fix: gnome-doc-utils is removed from Debian Bullseye

[Guillaume Bernard <gbernard src gnome org>]

commit a3c1a5f92f2850214a6a328a25fb5c9a9a930f6a
Author: Guillaume Bernard <associations guillaume-bernard fr>
Date:   Fri Sep 3 18:33:39 2021 +0200

    fix: gnome-doc-utils is removed from Debian Bullseye

 .gitlab-ci.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index c4defcfd..5d76232d 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -16,7 +16,7 @@ workflow:
 
 
 .debian-based-job:
-  image: python:latest
+  image: python:buster
   before_script:
     - apt update -qq
     - apt install -y -qq libicu-dev python3-icu python3-aeidon gettext intltool itstool yelp-tools yelp-xsl 
gnome-doc-utils