Update test gems and modernize setup

github-ds.gemspec

@@ -33,12 +33,10 @@ Gem::Specification.new do |spec|
   spec.add_dependency "activerecord", ">= 3.2"
 
   spec.add_development_dependency "bundler", ">= 1.14"
-  spec.add_development_dependency "rake", "~> 12.0"
-  spec.add_development_dependency "minitest", "~> 5.0"
-  spec.add_development_dependency "timecop", "~> 0.8.1"
+  spec.add_development_dependency "rake"
+  spec.add_development_dependency "minitest"
+  spec.add_development_dependency "timecop"
   spec.add_development_dependency "activesupport"
   spec.add_development_dependency "mysql2"
-  spec.add_development_dependency "mocha", "~> 1.2.1"
-  spec.add_development_dependency "minitest-focus", "~> 1.1.2"
-  spec.add_development_dependency "pry", "~> 0.12.2"
+  spec.add_development_dependency "mocha"
 end

test/test_helper.rb

@@ -1,15 +1,12 @@
-require "bundler/setup"
-require "pp"
+
 require "pathname"
 root_path = Pathname(File.expand_path("../..", __FILE__))
-$LOAD_PATH.unshift root_path.join("lib").to_s
+$LOAD_PATH.unshift File.expand_path("../lib", __dir__)
 require "github/ds"
 require "github/kv"
 require "timecop"
 require "minitest/autorun"
-require "mocha/mini_test"
-require "minitest/focus"
-require "pry"
+require "mocha/minitest"
 
 ActiveRecord::Base.configurations = {
   "without_database" => {