[ci] add checks on telemetry metrics exposed by the collectors

[atoulme]

Fixes #1071

[mowies]

I don't quite get why this test should be in the releases repo and not in the contrib repo directly next to the source code?

[atoulme]

I don't quite get why this test should be in the releases repo and not in the contrib repo directly next to the source code?

The last patch release was needed because a replace statement had to be added for contrib’s manifest. I expect that collector telemetry continues to be a sticking point.

[mowies]

ok then i guess it's good to have the tests here. I did create a separate pipeline for regression tests recently, maybe that could be used here as well

[atoulme]

ok then i guess it's good to have the tests here. I did create a separate pipeline for regression tests recently, maybe that could be used here as well

Is it this file? https://github.com/open-telemetry/opentelemetry-collector-releases/blob/main/.github/workflows/regression-tests.yaml
I am happy to piggy back on the current docker tests so we don't build the docker image twice.

[mowies]

either way is fine for me, i just wanted to mention it so you're aware of the option if it makes sense :)