[CI] Never skip required matrix-rollup jobs

[djaglowski]

Resolves #12334

The solution here works as follows:

The Matrix Job

• An output value is defined for each of the matrix jobs. By default, this value is empty.
• If a job does not succeed (failed, cancelled, or skipped) its output value is set to a non-empty value.

The Rollup Job

• Always runs.
• Concatenates all of the output values from the corresponding matrix jobs.
• If all of the output values are empty (all jobs passed), the concatenated value is empty as well.
• Success or failure of the rollup job is determined by evaluating whether the concatenated value is empty or not.

[djaglowski]

With the intentional failures introduced by the last change, the appropriate rollup jobs have all failed:

Links to failure messages:

• lint
• unittest (1.18
• unittest 1.17
• windows-unittest

[djaglowski]

With the intentional failures removed, everything passes as expected.

Direct links to rollup job validation steps:

• lint
• unittest (1.18)
• unittest (1.17)
• windows-unittest

[mx-psi]

Thank you for having a look Dan!

[mx-psi]

Looks like the rollup job can fail even if all jobs have passed https://github.com/open-telemetry/opentelemetry-collector-contrib/runs/7318709078?check_suite_focus=true

[mx-psi]

Revert PR: #12353, will wait in case there is an easy solution

[mx-psi]

It sounds like the issue only happens if you re-run failed jobs

[djaglowski]

Thanks @mx-psi. I think I have an idea for how to address this but I'll merge the reversion to ensure it's not blocking anyone while I test it.