ci: run the tests as a separate build stage

[DHowett]

This commit moves the unit and feature tests to a separate stage, which can be retried more easily.

Closes #11858

[zadjii-msft]

woah, that looks like it works. Thats so cool

[miniksa]

Oh thank goodness. This is exactly what I wanted.

[DHowett]

The way we're shuttling all exe/dll/etc artifacts from build to build scares me a little and we might want to use pipeline artifacts instead (docs say they're faster!), but... if you guys are cool with it I can be cool with it too

[zadjii-msft]

If it works, I'm cool with it

implying I really understand our ci config

[miniksa]

The way we're shuttling all exe/dll/etc artifacts from build to build scares me a little and we might want to use pipeline artifacts instead (docs say they're faster!), but... if you guys are cool with it I can be cool with it too

I honestly had no idea there were two different types of artifacts. So that should be a follow on investigation, IMO.

[DHowett]

I'm going to run the non-CI version against this to make sure Helix can still submit/report.

[DHowett]

yes, this works in helix. the tests fail, but submission works.

I should move helix submission to another sub-job