Fix: use correct image tag for Hugo build

.gitlab-ci.yml

@@ -3,8 +3,8 @@ variables:
   GIT_SUBMODULE_STRATEGY: recursive
 
 pages:
-  # This image is compatible with GitLab's shell-based runners
-  image: registry.gitlab.com/pages/hugo/hugo_extended:latest
+  # The new official standard image for Hugo extended
+  image: hugomods/hugo:exts
   script:
     - hugo version
     - hugo
@@ -12,4 +12,4 @@ pages:
     paths:
       - public
   rules:
-    - if: $CI_COMMIT_BRANCH == "master"
+    - if: $CI_COMMIT_BRANCH == $CI_COMMIT_REF_NAME