Update check_and_update_json_date.yml

.github/workflows/check_and_update_json_date.yml

@@ -13,7 +13,7 @@ jobs:
       - name: Checkout code
         uses: actions/checkout@v4
         with:
-          ref: ${{ github.head_ref }} 
+          ref: ${{ github.head_ref }}
 
       - name: Set up authentication
         env:
@@ -27,8 +27,8 @@ jobs:
       - name: Modify JSON files
         run: |
           TODAY=$(date -u +%Y-%m-%d)
-          # Filtern der geänderten Dateien im aktuellen PR
-          for json_file in $(git diff --name-only origin/main...$GITHUB_SHA | grep '.json$'); do
+          # Filtern der geänderten Dateien im aktuellen PR im Vergleich zum Basisbranch
+          for json_file in $(git diff --name-only ${{ github.base_ref }}...${{ github.head_ref }} | grep '.json$'); do
             if jq -e 'type == "object"' "$json_file" > /dev/null 2>&1; then
               jq --arg today "$TODAY" '.date_created = $today' "$json_file" > tmp.json && mv tmp.json "$json_file"
             fi