Update dependabot.yml

Author: baseplate-admin

.github/dependabot.yml

@@ -10,7 +10,7 @@ updates:
     schedule:
       interval: "monthly"
     open-pull-requests-limit: 100
-  - package-ecosystem: "actions" # See documentation for possible values
+  - package-ecosystem: "github-actions" # See documentation for possible values
     directory: "/" # Location of package manifests
     schedule:
       interval: "monthly"