update devise-two-factor to 4.0.0

Gemfile

@@ -27,7 +27,7 @@ gem "json-schema", "2.8.1"
 # Authentication
 
 gem "devise", "4.7.1"
-gem "devise-two-factor", "3.0.3"
+gem "devise-two-factor", "4.0.0"
 gem "devise_lastseenable", "0.0.6"
 gem "rqrcode", "1.1.2"
 

Gemfile.lock

@@ -174,12 +174,12 @@ GEM
       railties (>= 4.1.0)
       responders
       warden (~> 1.2.3)
-    devise-two-factor (3.0.3)
-      activesupport (< 5.3)
+    devise-two-factor (4.0.0)
+      activesupport (< 6.2)
       attr_encrypted (>= 1.3, < 4, != 2)
       devise (~> 4.0)
-      railties (< 5.3)
-      rotp (~> 2.0)
+      railties (< 6.2)
+      rotp (~> 6.0)
     devise_lastseenable (0.0.6)
       devise
       rails (>= 3.0.4)
@@ -616,7 +616,7 @@ GEM
       actionpack (>= 5.0)
       railties (>= 5.0)
     rexml (3.2.4)
-    rotp (2.1.2)
+    rotp (6.2.0)
     rqrcode (1.1.2)
       chunky_png (~> 1.0)
       rqrcode_core (~> 0.1)
@@ -805,7 +805,7 @@ DEPENDENCIES
   cucumber-rails (= 2.0.0)
   database_cleaner (= 1.8.3)
   devise (= 4.7.1)
-  devise-two-factor (= 3.0.3)
+  devise-two-factor (= 4.0.0)
   devise_lastseenable (= 0.0.6)
   diaspora-prosody-config (= 0.0.7)
   diaspora_federation-json_schema (= 0.2.6)

app/models/user.rb

@@ -4,6 +4,8 @@
 #   licensed under the Affero General Public License version 3 or later.  See
 #   the COPYRIGHT file.
 
+require "attr_encrypted"
+
 class User < ApplicationRecord
   include AuthenticationToken
   include Connecting