Tie llvm to emsdk's version

[mmitche]

This avoids incoherency that will cause the .NET build drop to be too large to fit on the staging pipeline disk.

[ghost]

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Issue Details

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This avoids incoherency that will cause the .NET build drop to be too large to fit on the staging pipeline disk.

Author:	mmitche
Assignees:	-
Labels:	area-Infrastructure-libraries
Milestone:	-

[lewing]

it looks like the subscription for llvm-project -> emsdk isn't set up properly and this is rolling back the version

cc @directhex @steveisok

[lewing]

I added the subscription

[lewing]

I updated to the latest build here so CI should go green again.

[mmitche]

Thanks!