Move token_in_session to helper method

app/controllers/projects/clusters/gcp_controller.rb

@@ -2,6 +2,7 @@ class Projects::Clusters::GcpController < Projects::ApplicationController
   before_action :authorize_read_cluster!
   before_action :authorize_create_cluster!, only: [:new, :create]
   before_action :authorize_google_api, except: :login
+  helper_method :token_in_session
 
   def login
     begin
@@ -59,7 +60,6 @@ class Projects::Clusters::GcpController < Projects::ApplicationController
   end
 
   def token_in_session
-    @token_in_session ||=
     session[GoogleApi::CloudPlatform::Client.session_key_for_token]
   end
 

app/views/projects/clusters/gcp/_form.html.haml

@@ -4,7 +4,7 @@
   - link_to_help_page = link_to(s_('ClusterIntegration|help page'), help_page_path('user/project/clusters/index'), target: '_blank', rel: 'noopener noreferrer')
   = s_('ClusterIntegration|Read our %{link_to_help_page} on Kubernetes cluster integration.').html_safe % { link_to_help_page: link_to_help_page}
 
-= form_for @cluster, html: { class: 'js-gke-cluster-creation prepend-top-20', data: { token: @token_in_session } }, url: gcp_namespace_project_clusters_path(@project.namespace, @project), as: :cluster do |field|
+= form_for @cluster, html: { class: 'js-gke-cluster-creation prepend-top-20', data: { token: token_in_session } }, url: gcp_namespace_project_clusters_path(@project.namespace, @project), as: :cluster do |field|
   = form_errors(@cluster)
   .form-group
     = field.label :name, s_('ClusterIntegration|Kubernetes cluster name')