feat: Configure cooldown for Dependabot updates (#440)

Added cooldown settings for npm and GitHub Actions updates.

Author: mfranzke

.github/dependabot.yml

@@ -9,6 +9,8 @@ updates:
       timezone: "Europe/Berlin"
     pull-request-branch-name:
       separator: "-"
+    cooldown:
+      default-days: 3
 
   # Daily: Check minor and patch updates
   - package-ecosystem: "npm"
@@ -25,6 +27,8 @@ updates:
       # We currently need to ignore eslint@v9
       - dependency-name: "eslint"
         update-types: ["version-update:semver-major"]
+    cooldown:
+      default-days: 3
     groups:
       patch-dependencies:
         update-types: