GRN2-xx: Switch the relation between users and roles to make queries cleaner and faster (#1299)

* First steps

* Fixes in account creation flow

* Fixed most testcases

* more test fixes

* Fixed more test cases

* Passing tests and rubocop

* Added rake task to remove rooms

config/locales/en.yml

@@ -534,7 +534,7 @@ en:
       provider: Provider
       image: Image
       image_url: Profile Image URL
-      roles: User Roles
+      roles: User Role
       subtitle: Update your Account Info
       title: Account Info
     delete:

config/routes.rb

@@ -94,7 +94,7 @@ Rails.application.routes.draw do
     get '/:user_uid/edit', to: 'users#edit', as: :edit_user
     get '/:user_uid/change_password', to: 'users#change_password', as: :change_password
     get '/:user_uid/delete_account', to: 'users#delete_account', as: :delete_account
-    patch '/:user_uid/edit', to: 'users#update', as: :update_user
+    post '/:user_uid/edit', to: 'users#update', as: :update_user
     delete '/:user_uid', to: 'users#destroy', as: :delete_user
 
     # All user recordings