gitlab-ci: remove rules:, it causes weird side effects

The use of rules: in 'fdroid build' seems to break the triggering of
'lint' and 'trigger-issuebot' and makes merge requests into "Detached
merge request pipelines".  This syncs the triggering setup between 'lint',
'fdroid build', and 'trigger-issuebot'.

.gitlab-ci.yml

@@ -2,10 +2,9 @@
 lint:
   image: registry.gitlab.com/fdroid/ci-images-base
   except:
-    refs:
-      - triggers
-      - schedules
-      - pipelines
+    - pipelines
+    - schedules
+    - triggers
   before_script:
     - printf "Package\x3a androguard fdroidserver python3-asn1crypto python3-ruamel.yaml yamllint\nPin\x3a release a=stretch-backports\nPin-Priority\x3a 500\n" > /etc/apt/preferences.d/debian-stretch-backports.pref
     - echo "deb http://deb.debian.org/debian/ stretch-backports main" > /etc/apt/sources.list.d/backports.list
@@ -67,7 +66,6 @@ trigger-issuebot:
     - master@fdroid/fdroiddata
     - pipelines
     - schedules
-    - tags
     - triggers
   variables:
     GIT_DEPTH: "1"
@@ -129,13 +127,11 @@ fdroid build:
       - unsigned/
     when: always
     expire_in: 1 month
-  rules:
-    - if: $CI_PIPELINE_SOURCE == "push" && $CI_COMMIT_BRANCH && $CI_PROJECT_PATH != "fdroid/fdroiddata"
-      changes:
-        - metadata/*.yml
-    - if: $CI_PIPELINE_SOURCE == "merge_request_event" && $CI_PROJECT_PATH != "fdroid/fdroiddata"
-      changes:
-        - metadata/*.yml
+  except:
+    - master@fdroid/fdroiddata
+    - pipelines
+    - schedules
+    - triggers
   cache:
     key: "$CI_JOB_NAME"
     paths: