Add option to disable two factor auth in admin accounts panel. (#2584)

* Add option to disable two factor auth in admin accounts panel.
Closes #2578

* Add @mjankowski's suggestions.
* Moves destroy actions behind User#disable_two_factor!
* Adds spec coverage for Admin:TwoFactorAuthenticationsController and User#disable_two_factor!

app/controllers/admin/two_factor_authentications_controller.rb

@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+module Admin
+  class TwoFactorAuthenticationsController < BaseController
+    before_action :set_user
+
+    def destroy
+      @user.disable_two_factor!
+      redirect_to admin_accounts_path
+    end
+
+    private
+
+    def set_user
+      @user = User.find(params[:user_id])
+    end
+  end
+end

app/models/user.rb

@@ -56,6 +56,12 @@ class User < ApplicationRecord
     confirmed_at.present?
   end
 
+  def disable_two_factor!
+    self.otp_required_for_login = false
+    otp_backup_codes&.clear
+    save!
+  end
+
   def send_devise_notification(notification, *args)
     devise_mailer.send(notification, self, *args).deliver_later
   end

app/views/admin/accounts/show.html.haml

@@ -70,6 +70,8 @@
 - if @account.local?
   %div{ style: 'float: right' }
     = link_to t('admin.accounts.reset_password'), admin_account_reset_path(@account.id), method: :create, class: 'button'
+    - if @account.user&.otp_required_for_login?
+      = link_to t('admin.accounts.disable_two_factor_authentication'), admin_user_two_factor_authentication_path(@account.user.id), method: :delete, class: 'button'
 
 %div{ style: 'float: left' }
   - if @account.silenced?