add cancan for authorization

app/controllers/submitters_send_email_controller.rb

@@ -1,18 +1,16 @@
 # frozen_string_literal: true
 
 class SubmittersSendEmailController < ApplicationController
+  load_and_authorize_resource :submitter, id_param: :submitter_slug, find_by: :slug
+
   def create
-    submitter = Submitter.joins(:template)
-                         .where(template: { account_id: current_account.id })
-                         .find_by!(slug: params[:submitter_slug])
+    SubmitterMailer.invitation_email(@submitter).deliver_later!
 
-    SubmitterMailer.invitation_email(submitter).deliver_later!
+    SubmissionEvent.create!(submitter: @submitter, event_type: 'send_email')
 
-    SubmissionEvent.create!(submitter:, event_type: 'send_email')
+    @submitter.sent_at ||= Time.current
+    @submitter.save!
 
-    submitter.sent_at ||= Time.current
-    submitter.save!
-
-    redirect_back(fallback_location: submission_path(submitter.submission), notice: 'Email has been sent')
+    redirect_back(fallback_location: submission_path(@submitter.submission), notice: 'Email has been sent')
   end
 end