chore: add dod and update abgrenzung.jpg

Author: deleonio

.github/dod.yml

@@ -0,0 +1,9 @@
+dod:
+  - Maturation completed and documented
+  - Meaningful pull request title for the release notes
+  - Pull request is linked to an issue
+  - All changes relate to the issue
+  - No TODOs or commented out code in the final commit
+  - Tests to protect this code implemented (if applicable)
+  - Manual test performed successfully (if applicable)
+  - Documentation or migration has been updated (if applicable)

.github/workflows/dod-checker.yml

@@ -0,0 +1,24 @@
+name: Definition of Done
+on:
+  pull_request:
+    types: [opened, edited, synchronize]
+
+concurrency:
+  group: pr-{{ github.event.pull_request.number }}
+  cancel-in-progress: true
+
+jobs:
+  check-dod:
+    runs-on: ubuntu-20.04
+    steps:
+      - name: Print Pull Request ID
+        run: |
+          echo "Pull Request Number: ${{ github.event.pull_request.number }}"
+      - name: Clone Repo
+        uses: actions/checkout@v3
+      - name: Check DoD
+        uses: platisd/definition-of-done@master
+        with:
+          dod_yaml: '.github/dod.yml'
+          message_header: 'The A11y and PO reviews will only take place after all other DoD steps have been completed by the Developer:'
+          github_token: ${{ secrets.GITHUB_TOKEN }}