Fix issues-auth.js

[miketaylr]

Blocks #2106.

Error fetching http://localhost:5000/issues/70
× firefox on darwin 17.4.0 - Issues (auth) - Pressing 'l' opens the label editor box (10.735s)
    NoSuchElement: [POST http://localhost:4444/wd/hub/session/b6b165cd-055b-8f4e-b9b1-24ac33e37532/element / {"using":"css selector","value":".wc-Issue-commentSubmit"}] Unable to locate element: .wc-Issue-commentSubmit
    For documentation on this error, please visit: http://seleniumhq.org/exceptions/no_such_element.html
    Build info: version: '3.5.2', revision: '10229a9020', time: '2017-08-21T17:54:21.164Z'
    System info: host: 'omg-5', ip: '192.168.2.83', os.name: 'Mac OS X', os.arch: 'x86_64', os.version: '10.13.3', java.version: '1.8.0_144'
    Driver info: driver.version: unknown
      at Object.openPage  <tests/functional/lib/helpers.js:27:8>
      at Test.Pressing 'l' opens the label editor box [as test]  <tests/functional/issues-auth.js:25:32>
      at <src/lib/Test.ts:260:47>
      at Command.<anonymous>  <tests/functional/lib/helpers.js:36:12>
      at Object.openPage  <tests/functional/lib/helpers.js:29:8>
      at Test.Pressing 'l' opens the label editor box [as test]  <tests/functional/issues-auth.js:25:32>
      at <src/lib/Test.ts:260:47>

TOTAL: tested 1 platforms, 0 passed, 1 failed