title: slack app channel:history scope works only in one workspace
body: <p>I have a few workspaces in my slack.
  each workspace has the same app installed in it.</p>
  <p>I'm trying to use <code>channel:history</code> scope for getting a <code>message</code> event.</p>
  <p>the issue is that its works only in one workspace, the workspace mentioned in Your Apps list: <a href="https://api.slack.com/apps" rel="nofollow noreferrer">My Apps</a>.
  for all other workspaces there is a <code>scope missing</code> Error.</p>
  <p>each app works only for the mentioned workspace <a href="https://i.stack.imgur.com/7r3Dl.png" rel="nofollow noreferrer">ass seen here</a> .</p>
  <p>Why is this happening?</p>