NoMethodError: undefined method `map' for ";print(md5(31337));$a=":String

https://sentry.gitlab.net/gitlab/gitlabcom/issues/3316944/?referrer=gitlab_plugin

NoMethodError: undefined method `map' for ";print(md5(31337));$a=":String
Did you mean?  tap
  app/controllers/graphql_controller.rb:175:in `multiplex_queries'
    params[:_json].map do |single_query_info|
  app/controllers/graphql_controller.rb:160:in `execute_multiplex'
    GitlabSchema.multiplex(multiplex_queries, context: context)
  app/controllers/graphql_controller.rb:57:in `execute'
    result = multiplex? ? execute_multiplex : execute_query
  app/controllers/application_controller.rb:531:in `set_current_admin'
    return yield unless Gitlab::CurrentSettings.admin_mode
  lib/gitlab/i18n.rb:107:in `with_locale'
    yield
...
(146 additional frame(s) were not displayed)