title: Ensure that done() callback is being called in this Mocha test
body: <p>Looking at other questions, can't really find the cause of the problem. I am trying to test using mocha.</p>
  
  <pre><code>it("Should not do the work",function(done) {
    axios
      .post("x/y",{ id:a2 })
      .then(function(res) {
        assert(false,"Should not do the work");
        done();
      })
      .catch(function(res) {
        assert.equal(HttpStatus.CONFLICT,res.status);
        done();
      });
  });
  
  it("Should do the work",function(done) {
    axios
      .post("/x/y",{ id: a1 })
      .then(function(res) {
        done();
      })
      .catch(done);
  });
  </code></pre>
  
  <p>The result was:</p>
  
  <pre><code>√ Should not do the work (64ms)
  1) Should do the work
  1 passing (20s)
  1 failing
  
  1) Error: Timeout of 20000ms exceeded. For async tests and hooks, ensure "done()" is called; if returning a Promise, ensure it resolves.
  </code></pre>
  
  <p>Increasing the timeout didn't work.</p>