Revert "Update dependabot config"

Tests don't work properly with github actions update and can't be detected by dependabot/fetch-metadata

dependabot/fetch-metadata#76

This reverts commit 4f9051b.

.github/dependabot.yml

@@ -1,6 +1,5 @@
 version: 2
 updates:
-
   - package-ecosystem: npm
     directory: "/"
     schedule:
@@ -13,10 +12,3 @@ updates:
         dependency-name: "caniuse-lite"
     versioning-strategy: increase
     open-pull-requests-limit: 10
-
-  - package-ecosystem: github-actions
-    directory: "/"
-    schedule:
-      interval: daily
-      time: "08:00"
-      timezone: "Asia/Tokyo"