Elvis has too many domains and none of them are good

[GuySartorelli]

Currently elvis has a number of different domains, some of which are even hosting different content:

1. https://github-issue-search-client-silverstripe.vercel.app/
   • This is what vercel auto-deploys to when stuff is merged in.
2. https://silverstripe-github-issues.vercel.app/
   • Seems to be using an outdated codebase, so must be hosted separately somewhere
3. https://silverstripe-github-issues.now.sh/
   • This is what the docs (indirectly, via redirector pages on .org) point to
   • Redirects to 2 above
4. http://silverstripe-issue-tracker.silverstripe.org/
   • A half decent subdomain which redirects to 1 above.
   • No ssl cert, so https links make the browser grumpy.

Epic

• https://github.com/silverstripe/.github/issues/141

Acceptance Criteria

• Only one version of the vercel app exists
• We have a good subdomain that we can easily refer to in docs
• The subdomain doesn't redirect anywhere, it's the direct URL for the application
• The subdomain has a valid SSL cert, and accessing http redirects to https
• Links in docs are updated to use the new subdomain instead of redirector page URLs
• Issue and PR templates link to elvis wherever they encourage people to look for existing issues
• The new subdomain is called out in the triage and peer review page

[GuySartorelli]

Closed as a duplicate of https://github.com/silverstripe/github-issue-search-client/issues/139 which will handle this along with a few other things