ci: Switch to using new rules syntax

The rules syntax is more clear and explicit than the previous
only/except. Switch to using that.

Signed-off-by: Daniel Stone <daniels@collabora.com>

.gitlab-ci.yml

@@ -24,9 +24,14 @@ stages:
     FDO_DISTRIBUTION_EXEC: 'bash .gitlab-ci/debian-install.sh'
     FDO_DISTRIBUTION_TAG: '2021-07-31.0-pipewire'
 
+.ci-rules:
+  rules:
+    - when: on_success
+
 
 container_prep:
   extends:
+    - .ci-rules
     - .debian
     - .fdo.container-build@debian
   timeout: 30m
@@ -35,6 +40,7 @@ container_prep:
 
 .build-env:
   extends:
+    - .ci-rules
     - .debian
     - .fdo.distribution-image@debian
   timeout: 5m
@@ -140,6 +146,7 @@ build-no-gl:
 
 docs-and-coverage:
   extends:
+    - .ci-rules
     - .debian
     - .fdo.distribution-image@debian
   stage: pages
@@ -160,6 +167,7 @@ docs-and-coverage:
     - Documentation/
     - Test_Coverage/
 
+# does not inherit .ci-rules
 pages:
   extends:
     - .debian
@@ -175,5 +183,7 @@ pages:
   artifacts:
     paths:
     - public
-  only:
+  rules:
-    - main
+    - if: '$CI_PIPELINE_SOURCE == "push" && $CI_PROJECT_PATH == "wayland/weston" && $CI_BUILD_REF_NAME == $CI_DEFAULT_BRANCH'
+      when: on_success
+    - when: never