title: Update gem on staging server only
body: <p>I want to update one of my gems on staging server ONLY. So, I'm running</p>
  
  <pre><code>bundle update gemname
  </code></pre>
  
  <p>or</p>
  
  <pre><code>bundle install
  </code></pre>
  
  <p>but then I got error:</p>
  
  <pre><code>You have modified your Gemfile in development but did not check the resulting snapshot (Gemfile.lock) into version control
  </code></pre>
  
  <p>The problem is that I can't do it locally and I can't push it into git repository. Any ideas how to solve it?</p>