Fix false positive when using chai-as-promised

[fflorent]

The issue

When we use both chai-as-promised and chai-xml, chai-xml inhibits the behavior of chai-as-promised with the eventually keyword.

eventually has to be used in a return statement so we can test the promise result.

Steps to reproduce

1. Download the attached project: foo.zip
2. Unzip and inside the foo/ folder, run npm install
3. Run the below command:

$ ./node_modules/mocha/bin/mocha ./index-spec.js

Actual Result

  Fancy describe
    ✓ should fail
(node:9563) UnhandledPromiseRejectionWarning: AssertionError: expected 4 to equal 3
    at /tmp/foo/node_modules/chai-as-promised/lib/chai-as-promised.js:302:22
    at processTicksAndRejections (internal/process/task_queues.js:97:5)
    ....

Expected result

(You can comment chai.use(require("chai-xml")); in index-spec.js to see the expected result)

  Fancy describe
    1) should fail


  0 passing (6ms)
  1 failing

  1) Fancy describe
       should fail:

      AssertionError: expected 4 to equal 3
      + expected - actual

      -4
      +3
      
      at /tmp/foo/node_modules/chai-as-promised/lib/chai-as-promised.js:302:22

Explanation of the patch

Simply use the return statement to make a clean by-pass to other hooks.

[krampstudio]

@fflorent I've included it in the version 0.4.0