title: Using pm2 to do yarn start gives error while npm start works fine
body: <p>I have a NodeJs microservice. Doing yarn start normally works perfectly fine. When I try to use pm2 to start this as a background service, facing the below issue:</p>
  
  <pre><code>/Users/sairamk/.pm2/logs/api-error-21.log last 15 lines:
  21|api     | /usr/local/Cellar/yarn/0.27.5_1/bin/yarn:2
  21|api     | PREFIX="/usr/local" exec "/usr/local/Cellar/yarn/0.27.5_1/libexec/bin/yarn.js" "$@"
  21|api     |                     ^^^^
  21|api     |
  21|api     | SyntaxError: Unexpected identifier
  21|api     |     at createScript (vm.js:74:10)
  21|api     |     at Object.runInThisContext (vm.js:116:10)
  21|api     |     at Module._compile (module.js:533:28)
  21|api     |     at Object.Module._extensions..js (module.js:580:10)
  21|api     |     at Module.load (module.js:503:32)
  21|api     |     at tryModuleLoad (module.js:466:12)
  21|api     |     at Function.Module._load (module.js:458:3)
  21|api     |     at Object.&lt;anonymous&gt; (/usr/local/lib/node_modules/pm2/lib/ProcessContainerFork.js:70:21)
  21|api     |     at Module._compile (module.js:569:30)
  21|api     |     at Object.Module._extensions..js (module.js:580:10)
  </code></pre>
  
  <p>PM2 command that I use:</p>
  
  <pre><code>pm2 start yarn --name api -- start
  </code></pre>
  
  <p>while npm start for the same, works fine with below command :</p>
  
  <pre><code>pm2 start npm --name api -- start
  </code></pre>
  
  <p>Tried exploring many possibilities. What am I doing wrong ?</p>