Add notification support for travis-ci.com

Bug Report

SUMMARY

Projects in Travis CI has been migrated from travis-ci.org to travis-ci.com and notifications does no longer work but instead HTTP 400 is returned from the notification API.

I have again went through the instructions listed in the documentation: https://docs.ansible.com/ansible/latest/reference_appendices/galaxy.html#travis-integrations

STEPS TO REPRODUCE

Do not know a good way to reproduce it more than doing a commit in github and wait for Travis CI to send a webhook notification.

EXPECTED RESULTS

Import triggered in Ansible Galaxy

ACTUAL RESULTS

No trigger seen in Ansible Galaxy and Travis CI got 400 error.

Got a log from Travis CI support to just show that the API returns 400. They also say they seen these kind of errors on other projects since at least 5th of June:

Jun 07 09:21:19 UTC task=webhook status=error build=75601644 url=https://galaxy.ansible.com/api/v1/notifications/ error_code=400 message="detail" 

Travis CI webhook payload can be seen here: https://github.com/travis-ci/travis-tasks/blob/b70c47a4935f3c3ecb3d096e5ad39c56d7d6f465/lib/travis/addons/webhook/payload.rb

[haxorof]

@chouseknecht Now I have tested it two times against Galaxy QA and it works like a charm. Good work!

[haxorof]

@chouseknecht Sorry not answering earlier but I will see if I can test this some time today or tomorrow.