Remove upper limit for rails dependency

Co-Authored-By: jacobbednarz <[email protected]>

Author: rafaelfranca

test/fixtures/engine_project/engine_project.gemspec

@@ -15,7 +15,7 @@ Gem::Specification.new do |s|
   s.files = Dir["{app,config,db,lib}/**/*", "MIT-LICENSE", "Rakefile", "README.rdoc"]
   s.test_files = Dir["test/**/*"]
 
-  s.add_dependency "rails", ">= 4.0.0.beta", "< 7"
+  s.add_dependency "rails", ">= 4.0.0.beta"
   # s.add_dependency "jquery-rails"
 
   s.add_development_dependency "sqlite3"