title: "git push --mirror" fails to push some refs, are the other refs being pushed correctly?
body: <p>I'm migrating git repos between two systems and I'm wondering if when a <code>git push --mirror</code> fails to push some refs, the other refs are pushed successfully...</p>
  <p>For example, I'm receiving an output like this for my git push:</p>
  <pre><code>   eaa296537..f8ee5c121  master -&gt; master
   - [deleted]             20200619.2.dev
   - [deleted]             20200619.3.dev
   * [new branch]          feature/mailing -&gt; feature/mailing
   * [new tag]             20200626.5.dev -&gt; 20200626.5.dev
   * [new tag]             20200626.6.dev -&gt; 20200626.6.dev
   ! [remote rejected]     refs/pull/11/merge (The current action can only be performed by the system
   ! [remote rejected]     refs/pull/4/merge (The current action can only be performed by the system
   ! [remote rejected]     refs/pull/6/merge (The current action can only be performed by the system
  error: failed to push some refs to 'https://dev.azure.com/TEST'
  </code></pre>
  <p>Are the other branches and tags being actually pushed?</p>