Categorize GraphQL schema and auto generated docs files

lib/gitlab/danger/helper.rb

@@ -200,6 +200,9 @@ module Gitlab
         %r{\Alocale/gitlab\.pot\z} => :none,
         %r{\Adata/whats_new/} => :none,
 
+        # GraphQL auto generated doc files and schema
+        %r{\Adoc/api/graphql/reference/} => :backend,
+
         # Fallbacks in case the above patterns miss anything
         %r{\.rb\z} => :backend,
         %r{(

spec/lib/gitlab/danger/helper_spec.rb

@@ -312,6 +312,8 @@ RSpec.describe Gitlab::Danger::Helper do
 
       'db/fixtures/foo.rb'                                 | [:backend]
       'ee/db/fixtures/foo.rb'                              | [:backend]
+      'doc/api/graphql/reference/gitlab_schema.graphql'    | [:backend]
+      'doc/api/graphql/reference/gitlab_schema.json'       | [:backend]
 
       'qa/foo' | [:qa]
       'ee/qa/foo' | [:qa]