Update submodules on pipeline run

.drone.yml

@@ -9,6 +9,21 @@ trigger:
       - push
 
 steps:
+  - name: Abort if CI Commit
+    image: registry.tobiasmanske.de/git:latest
+    commands:
+      - "[[ \"$${GIT_COMMITTER_NAME}\" = \"Drone CI\" ]] && exit 78"
+      - exit 0
+
+  - name: Update submodules
+    image: registry.tobiasmanske.de/git:latest
+    commands:
+      - git config user.name "Drone CI"
+      - git config user.email "noreply@tobiasmanske.de"
+      - git submodule update --remote --merge
+      - git add -A
+      - git commit -m "Update submodules from CI"
+      - git push
   - name: Start buildpipeline
     image: plugins/downstream
     settings:
@@ -20,3 +35,6 @@ steps:
         - archlinux-repo/builder
       params:
         - "NO_GIT_REBUILD=true"
+
+image_pull_secrets:
+  - registry