Allow bundler 4

Author: fnordfish

teckel.gemspec

@@ -30,7 +30,7 @@ Gem::Specification.new do |spec|
 
   spec.required_ruby_version = ">= 2.4.0"
 
-  spec.add_development_dependency "bundler", "~> 2.0"
+  spec.add_development_dependency "bundler", ">= 2.0"
   spec.add_development_dependency "rake", ">= 10.0"
   spec.add_development_dependency "rspec", "~> 3.0"
   spec.add_development_dependency "mutant-rspec"