dependabot for branch archiva-2.x as well

.github/dependabot.yml

@@ -19,8 +19,15 @@ version: 2
 updates:
   - package-ecosystem: "maven"
     directory: "/"
+    target-branch: "master"
     schedule:
       interval: "daily"
+      
+  - package-ecosystem: "maven"
+    directory: "/"
+    target-branch: "archiva-2.x"
+    schedule:
+      interval: "daily"      
 
   - package-ecosystem: "github-actions"
     directory: "/"