Make tests green on jruby

Author: flori

json.gemspec

@@ -8,7 +8,7 @@ Gem::Specification.new do |s|
   s.required_rubygems_version = Gem::Requirement.new(">= 0".freeze) if s.respond_to? :required_rubygems_version=
   s.require_paths = ["lib".freeze]
   s.authors = ["Florian Frank".freeze]
-  s.date = "2019-12-09"
+  s.date = "2019-12-10"
   s.description = "This is a JSON implementation in pure Ruby.".freeze
   s.email = "flori@ping.de".freeze
   s.extra_rdoc_files = ["README.md".freeze]

json_pure.gemspec

@@ -49,6 +49,7 @@ def silence
   end
 
   def test_remove_const_segv
+    return if RUBY_ENGINE == 'jruby'
     stress = GC.stress
     const = JSON::SAFE_STATE_PROTOTYPE.dup