Update rails (#251)

* Rails 8.0 support

* Update to Bot API 8.0

telegram-bot.gemspec

@@ -25,8 +25,8 @@ Gem::Specification.new do |spec|
 
   spec.required_ruby_version = '>= 2.4'
 
-  spec.add_dependency 'actionpack', '>= 4.0', '< 7.3'
-  spec.add_dependency 'activesupport', '>= 4.0', '< 7.3'
+  spec.add_dependency 'actionpack', '>= 4.0', '< 8.1'
+  spec.add_dependency 'activesupport', '>= 4.0', '< 8.1'
   spec.add_dependency 'httpclient', '~> 2.7'
 
   spec.add_development_dependency 'bundler', '> 1.16'