ci: group eslint config updates

Author: freaktechnik

.github/dependabot.yml

@@ -8,6 +8,11 @@ updates:
       prefix: "chore:"
     open-pull-requests-limit: 5
     versioning-strategy: "increase"
+    groups:
+      eslint-configs:
+        dependency-type: "development"
+        patterns:
+        - "@freaktechnik/eslint-config*"
   - package-ecosystem: "github-actions"
     directory: "/"
     schedule: