ci: switch to native change detection

.gitea/workflows/cd.yaml

@@ -4,35 +4,16 @@ on:
   push:
     branches:
       - main
+    paths:
+      - "src/**"
+      - "Dockerfile"
 
 env:
   DOCKER_REGISTRY: gitea.t000-n.de
 
 jobs:
-  check-changes:
-    name: Check changes
-    runs-on: ubuntu-latest
-    outputs:
-      changes: ${{ steps.filter.outputs.code }}
-    steps:
-      - name: Checkout
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
-
-      - name: Get changed files
-        id: filter
-        uses: dorny/paths-filter@de90cc6fb38fc0963ad72b210f1f284cd68cea36 # v3.0.2
-        with:
-          filters: |
-            code:
-              - 'src/**'
-              - 'Dockerfile'
-              - 'gitea/workflows/**'
-
   build_and_push:
     name: Build and push
-    needs:
-      - check-changes
-    if: ${{ needs.check-changes.outputs.changes != '0' }}
     strategy:
       matrix:
         arch: