build: update Appraisals dependencies

Appraisals

@@ -1,17 +1,5 @@
 # frozen_string_literal: true
 
-appraise 'rails60-activeadmin22' do
-  gem 'activeadmin', '~> 2.2.0'
-  gem 'rails', '~> 6.0.0'
-  gem 'selenium-webdriver', require: false
-end
-
-appraise 'rails60-activeadmin' do
-  gem 'activeadmin'
-  gem 'rails', '~> 6.0.0'
-  gem 'selenium-webdriver', require: false
-end
-
 appraise 'rails61-activeadmin29' do
   gem 'activeadmin', '~> 2.9.0'
   gem 'rails', '~> 6.1.0'
@@ -27,3 +15,9 @@ appraise 'rails70-activeadmin' do
   gem 'rails', '~> 7.0.0'
   gem 'sprockets-rails'
 end
+
+appraise 'rails71-activeadmin' do
+  gem 'activeadmin'
+  gem 'rails', '~> 7.1.0'
+  gem 'sprockets-rails'
+end