title: github 'resolve conflicts' button disabled
body: <p>I'm an admin on this repo. In this PR I have removed multiple files and merged these changes from local to origin/develop. When merging origin/develop to origin/master I'm getting this conflict for one of the four files I've removed. Our flow is always local to origin/develop to origin/master. I had no conflicts when mergin local to origin/develop.
  Github won't let me resolve the conflict.</p>
  
  <p>Questions:</p>
  
  <ol>
  <li><p>Why is the  'Resolve Conflicts' button disabled? I've never seen this before.</p></li>
  <li><p>Why would this one file have a merge conflict? It's one of 3 config files that I removed completely in this PR.</p></li>
  <li>Why am I getting this conflict on origin/develop to origin/master when I had no conflicts on local to origin/develop?</li>
  </ol>
  
  <p><a href="https://i.stack.imgur.com/iy0GI.png" rel="noreferrer"><img src="https://i.stack.imgur.com/iy0GI.png" alt="enter image description here"></a></p>