Fix a typo in spec

spec/factories/clusters/applications/helm.rb

@@ -49,7 +49,7 @@ FactoryBot.define do
       cluster factory: %i(cluster with_installed_helm provided_by_gcp)
     end
 
-    factory :clusters_applications_cert_manager, class: Clusters::Applications::CertManager do
+    factory :clusters_applications_cert_managers, class: Clusters::Applications::CertManager do
       email 'admin@example.com'
       cluster factory: %i(cluster with_installed_helm provided_by_gcp)
     end