[gimp-help/wip/wormnest/validate] ci: install python3-polib needed by validate_po.py

[Jacob Boerema <jboerema src gnome org>]

commit c11487b165f405df35c4e131b64ef19d2759a963
Author: Jacob Boerema <jgboerema gmail com>
Date:   Sat Jul 23 13:34:22 2022 -0400

    ci: install python3-polib needed by validate_po.py

 .gitlab-ci.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index f7cf7b378..a33a1f816 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -25,7 +25,7 @@ build-image:
     - echo "FROM debian:testing" > Dockerfile
     - echo "RUN apt-get update" >> Dockerfile
     - echo "RUN apt-get install -y --no-install-recommends \\" >> Dockerfile
-    - echo "automake build-essential docbook-website docbook-xml docbook-xsl fonts-noto-cjk gettext intltool 
librsvg2-2 librsvg2-bin pkg-config pngcrush python3 python3-libxml2 xsltproc" >> Dockerfile
+    - echo "automake build-essential docbook-website docbook-xml docbook-xsl fonts-noto-cjk gettext intltool 
librsvg2-2 librsvg2-bin pkg-config pngcrush python3 python3-libxml2 python3-polib xsltproc" >> Dockerfile
 
     - /kaniko/executor --context $CI_PROJECT_DIR --dockerfile $CI_PROJECT_DIR/Dockerfile --destination 
$CI_REGISTRY_IMAGE:build-debian-latest --cache=true --cache-ttl=120h