Add cooldown configuration for package ecosystems in dependabot.yml (#1666)

Co-authored-by: Garry Trinder <garry@trinder365.co.uk>

Author: waldekmastykarz

.github/dependabot.yml

@@ -7,13 +7,19 @@ updates:
     - "/DevProxy.Plugins"
   schedule:
     interval: daily
+  cooldown:
+    default-days: 7
 
 - package-ecosystem: "docker"
   directory: "/"
   schedule:
     interval: daily
+  cooldown:
+    default-days: 7
 
 - package-ecosystem: "github-actions"
   directory: "/"
   schedule:
-    interval: daily
+    interval: daily
+  cooldown:
+    default-days: 7