ci: configure monthly Dependabot updates

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Author: daquinoaldo

.github/dependabot.yml

@@ -0,0 +1,27 @@
+version: 2
+updates:
+  - package-ecosystem: npm
+    directory: /
+    schedule:
+      interval: monthly
+      day: 1
+      time: "09:00"
+      timezone: Europe/Rome
+    open-pull-requests-limit: 1
+    groups:
+      dependencies:
+        patterns:
+          - "*"
+
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+      interval: monthly
+      day: 1
+      time: "09:00"
+      timezone: Europe/Rome
+    open-pull-requests-limit: 1
+    groups:
+      github-actions:
+        patterns:
+          - "*"