[release/8.0-staging] Transition to 1ES templates work (Backport crossgen2 changes)

[eduardo-vp]

This is part of the work to transition to the 1ES templates in servicing branches.

These crossgen2 changes are required to eventually backport #92901.

Official build (64c851b): https://dev.azure.com/dnceng/internal/_build/results?buildId=2447759&view=results

cc @jkoritzinsky @agocke @amanasifkhalid

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[eduardo-vp]

Official build (f834323): https://dev.azure.com/dnceng/internal/_build/results?buildId=2444879&view=results

[eduardo-vp]

Official build (64c851b): https://dev.azure.com/dnceng/internal/_build/results?buildId=2447759&view=results

[agocke]

Could you elaborate a bit on what's required here? It's not clear to me why we need crossgen2 changes.

[jkoritzinsky]

The crossgen2 changes are needed to avoid the build/restore for publishing crossgen2 while also building it in the repo related to finding host artifacts correctly (there's conflicts around finding hosting artifacts when NativeAOT is supported).

The test official build for backporting #92901 exposed these issues, and @eduardo-vp and I feel that backporting the criossgen2 changes will fix those problems.

[agocke]

Makes sense. I will review to try to ensure that all the pieces we've changed are backported.

[eduardo-vp]

I just checked that the issues exposed in the test official build @jkoritzinsky mentioned are effectively solved by applying these commits (Official build before https://dev.azure.com/dnceng/internal/_build/results?buildId=2445418&view=results and after https://dev.azure.com/dnceng/internal/_build/results?buildId=2448441&view=results)

[agocke]

LGTM

[jeffschwMSFT]

lgtm. let's consider this tell mode. please merge when ready

cc @carlossanlop