rexml is no longer default gem in Ruby 3.0

Gemfile

@@ -27,6 +27,10 @@ gem 'jbuilder', '~> 2.7'
 
 gem 'nokogiri'
 
+# rexml is no longer default gem in Ruby 3.0
+# https://github.com/rails/rails/commit/c23533ee0b50fdc67cc73b579674637ba6f34cb4
+gem 'rexml'
+
 gem 'elasticsearch-persistence'
 gem 'elasticsearch-rails'
 

Gemfile.lock

@@ -203,6 +203,7 @@ GEM
       ffi (~> 1.0)
     redis (4.2.5)
     regexp_parser (1.8.2)
+    rexml (3.2.4)
     ruby2_keywords (0.0.2)
     rubyzip (2.3.0)
     sass-rails (6.0.0)
@@ -277,6 +278,7 @@ DEPENDENCIES
   pry
   puma (~> 5.1)
   rails (~> 6.1.0)
+  rexml
   sass-rails (>= 6)
   selenium-webdriver
   sidekiq