title: Difference between git commit --amend and git rebase under gerrit
body: <p>I want to change the last commit content.
  I can do local changes.
  and then execute</p>
  
  <pre><code>git commit --amend
  </code></pre>
  
  <p>I can also do the following:</p>
  
  <pre><code>git rebase -i HEAD~
  </code></pre>
  
  <p>choose the commit to edit.
  do local changes
  and then execute:</p>
  
  <pre><code>git rebase --continue
  </code></pre>
  
  <ol>
  <li>is there a difference between these two commands in this scenario ?</li>
  <li>in the context of Gerrit, when gerrit's CHANGE-ID is involved ?</li>
  </ol>