Batch Dependabot updates on a monthly basis

Author: rschmitt

.github/dependabot.yml

@@ -26,10 +26,13 @@ updates:
   - package-ecosystem: "maven"
     directory: "/"
     schedule:
-      interval: "weekly"
-      day: "friday"
+      interval: "monthly"
+    open-pull-requests-limit: 1
+    groups:
+      all:
+        patterns: ["*"]
   - package-ecosystem: "github-actions"
     directory: "/"
     schedule:
-      interval: "weekly"
-      day: "friday"
+      interval: "monthly"
+    open-pull-requests-limit: 1