Fix incorrect result right shifting specific negative BigInteger by 32 bits

[wzchua]

Fixes #27358

The issue was due to the 2's complement transformation when the big integer representation was [0xFFFFFFFF, 0xFFFFFFFF].
That becomes [0, 1]. and when you shift it by 32 bits you get [0]. so when you transform it back you still get 0 as the value

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Issue Details

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Fixes #27358

The issue was due to the 2's complement transformation when the big integer representation was [0xFFFFFFFF, 0xFFFFFFFF].
That becomes [0, 1]. and when you shift it by 32 bits you get [0]. so when you transform it back you still get 0 as the value

Author:	wzchua
Assignees:	-
Labels:	area-System.Numerics
Milestone:	-

[tannergooding]

This LGTM. However, could you please add a test covering the failing scenario?

CC. @pgovind for secondary review.

[wzchua]

The test is already there.

[tannergooding]

The test is already there.

So it is, I completely missed that file for some reason. Sorry for the confusion.

[jeffhandley]

/azp run runtime

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[jeffhandley]

As far as I can tell, this should be ready to merge once we get a green run from CI. I've restarted the run.

@tannergooding This PR is assigned to you for follow-up before the RC1 snap.

[pgovind]

LGTM

[jeffhandley]

Test failure is related to #56190.

[jeffhandley]

Thanks for the contribution, @wzchua!