Add CLI#run_job

spec/cli_spec.rb

@@ -1,6 +1,10 @@
 require "spec_helper"
 require 'crono/cli'
 
+class TestJob
+  def perform;end
+end
+
 describe Crono::CLI do
   let(:cli) { Crono::CLI.instance }
 
@@ -10,4 +14,11 @@ describe Crono::CLI do
       cli.run
     end
   end
+
+  describe "#run_job" do
+    it "should run job in separate thread" do
+      thread = cli.send(:run_job, TestJob).join
+      expect(thread).to be_stop
+    end
+  end
 end