Revert "Enable build on hosted arm64 (#40311)"

[ViktorHofer]

This reverts commit 176da26.

@omajid this broke the testing scenario as the ArchGroup defaults to x86 after this change. will revert this to unblock others and we can work on a follow-up change.

Discovered in https://github.com/dotnet/corefx/issues/40052#issuecomment-522498432

cc @Gnbrkm41 @Wraith2 @steveharter

[omajid]

Thanks for the quick fix. Any ideas on how CI could have caught this?

[joperezr]

We've had more internal reports of this @ViktorHofer so please do go ahead and merge this when you are ready.

[joperezr]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s), but failed to run 3 pipeline(s).

[joperezr]

@ViktorHofer FYI seems like your latest change to outerloop.yml broke the outerloop test run according to the above message. It is not blocking but I suppose you will want to either revert that or fix it as well.

[ViktorHofer]

@joperezr anybreason why you triggered the Outerloop legs here? Yeah I'm trying out a fix right now. Thanks for letting me know.

[joperezr]

anybreason why you triggered the Outerloop legs here?

Your builds were cancelled and I wasn't able to retry them on the AzDO side, so I ran the /azp run command from here to run everything, which also triggers the outerloop runs.

[ViktorHofer]

For that you want to use the /azp run corefx-ci command. The /azp run command triggers everything.