Unblock runtime publishing

[epananth]

• This issue is blocking
• This issue is causing unreasonable pain

Issue -> #6987

To temporarily unblock runtime publishing we are going to use a different build pool for publishing.

[MattGal]

@epananth and i chatted just now, we're going to synch with @riarenas . The thing about V3 publishing is that its choice of build pool is stuck in arcade's master branch, meaning we can't change this just for runtime ( I was thinking v2-style when I suggested it).

I think the risk is low (just changing the build pool) but there's a chance for delayed publishing for everyone while waiting for machines to spin up, and the things that wait on this might time out. As such, I'd like to get confirmation both from @epananth and @riarenas that we want to do this before proceeding.

[MattGal]

Created the test branch Ricardo suggested to limit this to just runtime, and this PR: dotnet/runtime#48521 to use it.

[MattGal]

Monitoring https://dnceng.visualstudio.com/internal/_build/results?buildId=1003468&view=results . Will put this into tracking if/when it succeeds.

[MattGal]

Moving to tracking.

[MattGal]

Just did this again: dotnet/runtime#48855

per @epananth it's looking like next week for a change that fixes this problem.

[MattGal]

@epananth can I assign this to you since you're doing the unblocking?

[ilyas1974]

@epananth, wanted to check in with you on this issue. Have we been able to roll out the fix for this?

[epananth]

I got my pr approved => #7086, will merge today...

[MattGal]

@epananth can I get a status update here?

[epananth]

I merged this PR. So far did not see any issues with the runtime publishing. I believe we are using the main branch to publish for runtime. We can close this issue.