Adds the ci_config dangerfile

danger/ci_config/Dangerfile

+# frozen_string_literal: true
+
+all_changed_files = helper.all_changed_files
+
+def get_ci_config_files(files)
+  files.select do |file|
+    file.include?('lib/gitlab/ci') 
+  end
+end
+
+schema_path = 'app/assets/javascripts/editor/schema/ci.json'
+ci_config_files = get_ci_config_files(all_changed_files)
+has_schema_update = all_changed_files.include?(schema_path)
+
+return if ci_config_files.empty? || has_schema_update;
+
+file_list = "- #{ci_config_files.map { |path| "`#{path}`" }.join("\n- ")}"
+
+warn "This merge request changed CI config files but did not update the schema. Please consider updating [the schema](#{schema_path}) to reflect these changes:\n#{file_list}"

tooling/danger/project_helper.rb

@@ -5,6 +5,7 @@ module Tooling
     module ProjectHelper
       LOCAL_RULES ||= %w[
         changelog
+        ci_config
         database
         documentation
         duplicate_yarn_dependencies