title: Jupyter Erroneous Environments Showing up in Conda tab with `nb_conda` extension
body: <p>Not sure how to fix this, or how it got corrupted. This is conda on a jupyterhub install. </p>
  
  <p>Error Message:</p>
  
  <blockquote>
    <p>EnvironmentLocationNotFound: Not a conda environment</p>
  </blockquote>
  
  <p>Pics Below:</p>
  
  <p>Image from <code>Conda</code> tab (there is an redundant <code>anaconda3</code> env showing up):</p>
  
  <p><a href="https://i.stack.imgur.com/1bm5l.png" rel="noreferrer"><img src="https://i.stack.imgur.com/1bm5l.png" alt="enter image description here"></a></p>
  
  <p>Image of error when loading:</p>
  
  <p><a href="https://i.stack.imgur.com/bP9fh.png" rel="noreferrer"><img src="https://i.stack.imgur.com/bP9fh.png" alt="enter image description here"></a></p>