Fix e-mail confirmations API not working correctly (#16348)

* Fix e-mail confirmations API not working correctly

* Fix typo

app/controllers/api/v1/emails/confirmations_controller.rb

@@ -3,12 +3,11 @@
 class Api::V1::Emails::ConfirmationsController < Api::BaseController
   before_action :doorkeeper_authorize!
   before_action :require_user_owned_by_application!
+  before_action :require_user_not_confirmed!
 
   def create
-    if !current_user.confirmed? && current_user.unconfirmed_email.present?
-      current_user.update!(email: params[:email]) if params.key?(:email)
-      current_user.resend_confirmation_instructions
-    end
+    current_user.update!(email: params[:email]) if params.key?(:email)
+    current_user.resend_confirmation_instructions
 
     render_empty
   end
@@ -18,4 +17,8 @@ class Api::V1::Emails::ConfirmationsController < Api::BaseController
   def require_user_owned_by_application!
     render json: { error: 'This method is only available to the application the user originally signed-up with' }, status: :forbidden unless current_user && current_user.created_by_application_id == doorkeeper_token.application_id
   end
+
+  def require_user_not_confirmed!
+    render json: { error: 'This method is only available while the e-mail is awaiting confirmation' }, status: :forbidden if current_user.confirmed? || current_user.unconfirmed_email.blank?
+  end
 end