chore: remove dependabot version-update config

cloudflare-worker/.github/dependabot.yml

@@ -1,19 +0,0 @@
-version: 2
-updates:
-  - package-ecosystem: "npm"
-    directory: "/"
-    schedule:
-      interval: "weekly"
-    open-pull-requests-limit: 10
-    groups:
-      minor-and-patch:
-        update-types: ["minor", "patch"]
-      security:
-        applies-to: security-updates
-        patterns: ["*"]
-    versioning-strategy: increase
-    labels: ["dependencies", "security"]
-  - package-ecosystem: "github-actions"
-    directory: "/"
-    schedule:
-      interval: "monthly"