Update dotnet SDK to latest published

[MattGal]

• You've read the Contributor Guide and Code of Conduct.
• You've included unit or integration tests for your change, where applicable. (N/a : updating global.json)
• You've included inline docs for your change, where applicable. (N/A)
• There's an open issue for the PR that you are making. If you'd like to propose a new feature or change, please open an issue to discuss the change or find an existing issue. (https://github.com/dotnet/core-eng/issues/13691)

PR Title
Update dotnet SDK to latest published

PR Description
This change brings an up update to take a threading fix that could improve the symptoms of https://github.com/dotnet/core-eng/issues/13691.

See issue for details; this is not necessarily the definitive fix, but something we need to try as the available data points to this as a likely culprit.

I'm making the same PR simultaneously in arcade, runtime, and aspnetcore in an effort to expedite the fix (if this is the fix) as well as exercise package restore in the places this is hitting most.

[Pilchie]

See #34819, where I think this is already happening. Ping @JunTaoLuo.

[MattGal]

See #34819, where I think this is already happening. Ping @JunTaoLuo.

Awesome, not trying to step on @JunTaoLuo 's toes or anything. I'll let this finish (so I can see all the restore-from-azdo-public-feeds' outcomes) then close without merging.

[JunTaoLuo]

FYI, we should be ready to merge grpc/grpc-dotnet#1352 very soon.

[MattGal]

FYI, we should be ready to merge grpc/grpc-dotnet#1352 very soon.

Thanks @JunTaoLuo , I'll close this now. No repros of restore failure on the logs I noted.