chore: update dependabot target branch to dependabot/update-target

Author: MariusStorhaug

.github/dependabot.yml

@@ -7,6 +7,7 @@ version: 2
 updates:
   - package-ecosystem: github-actions # See documentation for possible values
     directory: / # Location of package manifests
+    target-branch: dependabot/update-target
     labels:
       - dependencies
       - github-actions