Remove upper dependency for activerecord

We are trying to test our application on rails 6.0.0.alpha but we can't install this because of the version lock
Probably this will be helpful that we can try and report any issues with edge rails

.travis.yml

@@ -16,6 +16,7 @@ env:
     - RAILS='~> 5.0.0'
     - RAILS='~> 5.1.0'
     - RAILS='~> 5.2.0'
+    - RAILS='master'
 
 matrix:
   allow_failures:
@@ -27,3 +28,10 @@ matrix:
       rvm: jruby-9.1.6.0
     - env: RAILS='~> 5.2.0'
       rvm: jruby-9.1.6.0
+    - env: RAILS='master'
+      rvm: jruby-9.1.6.0
+  exclude:
+    - rvm: 2.2
+      env: RAILS='master'
+    - rvm: 2.3.5
+      env: RAILS='master'

Gemfile

@@ -7,14 +7,18 @@ platforms :jruby do
 end
 
 platforms :rbx do
+  gem 'rubinius-developer_tools'
   gem 'rubysl', '~> 2.0'
   gem 'rubysl-test-unit'
-  gem 'rubinius-developer_tools'
 end
 
 rails = ENV['RAILS'] || '~> 5.2.0'
 
-gem 'rails', rails
+if rails == 'master'
+  gem 'rails', github: 'rails/rails'
+else
+  gem 'rails', rails
+end
 
 # Specify your gem's dependencies in paranoia.gemspec
 gemspec

lib/paranoia.rb

 require 'active_record' unless defined? ActiveRecord
 
-if [ActiveRecord::VERSION::MAJOR, ActiveRecord::VERSION::MINOR] == [5, 2]
+if [ActiveRecord::VERSION::MAJOR, ActiveRecord::VERSION::MINOR] == [5, 2] ||
+   ActiveRecord::VERSION::MAJOR > 5
   require 'paranoia/active_record_5_2'
 end
 
@@ -305,7 +306,7 @@ module ActiveRecord
     class UniquenessValidator < ActiveModel::EachValidator
       prepend UniquenessParanoiaValidator
     end
-    
+
     class AssociationNotSoftDestroyedValidator < ActiveModel::EachValidator
       def validate_each(record, attribute, value)
         # if association is soft destroyed, add an error

paranoia.gemspec

@@ -24,7 +24,7 @@ Gem::Specification.new do |s|
 
   s.required_ruby_version = '>= 2.0'
 
-  s.add_dependency 'activerecord', '>= 4.0', '< 5.3'
+  s.add_dependency 'activerecord', '>= 4.0'
 
   s.add_development_dependency "bundler", ">= 1.0.0"
   s.add_development_dependency "rake"