Fixes & small tweaks for Github deployment triggers

We just fixed some bugs and usability/reliability issues with Github deployment triggers.

  1. Environment URLS containing dashes "-" were sometimes not parsed and replaced correctly in API check URL's.

  2. Our queue worker behaved unreliably during maintenance. We moved our queue to a more reliable solution.

  3. We fixed some layout issues in the Github "check" markdown you see in your PR's and commits. We now also report the environment URL used in the Github check.