Merge pull request #4054 from rubygems/lock-parallel-gem

Lock parallel ~> 1.19.2

(cherry picked from commit fc75358)

bundler/spec/commands/newgem_spec.rb

@@ -14,6 +14,7 @@ def bundle_exec_rubocop
     prepare_gemspec(bundled_app(gem_name, "#{gem_name}.gemspec"))
     rubocop_version = RUBY_VERSION > "2.4" ? "0.90.0" : "0.80.1"
     gems = ["minitest", "rake", "rake-compiler", "rspec", "rubocop -v #{rubocop_version}", "test-unit"]
+    gems.unshift "parallel -v 1.19.2" if RUBY_VERSION < "2.5"
     gems += ["rubocop-ast -v 0.4.0"] if rubocop_version == "0.90.0"
     path = Bundler.feature_flag.default_install_uses_path? ? local_gem_path(:base => bundled_app(gem_name)) : system_gem_path
     realworld_system_gems gems, :path => path