Change dependabot configuration

Author: seijikohara

.github/dependabot.yml

@@ -1,6 +1,10 @@
 version: 2
 updates:
-- package-ecosystem: npm
-  directory: "/"
-  schedule:
-    interval: daily
+  - package-ecosystem: "npm"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "weekly"