Bring back Dependabot cooldown on github actions (DataDog#22842)

Author: AAraKKe

.github/dependabot.yml

@@ -8,6 +8,8 @@ updates:
       interval: "weekly"
       day: "monday"
       time: "06:00"
+    cooldown:
+      default-days: 7
     # Group all actions updates together in the same PR
     groups:
       actions:
@@ -23,7 +25,8 @@ updates:
       interval: "weekly"
       day: "monday"
       time: "06:00"
-    # Group all actions updates together in the same PR
+    cooldown:
+      default-days: 7
     groups:
       actions:
         patterns: