Add System.Linq Chunk extension method

[inputfalken]

Fix #27449

Some things I would especially like feedback on is:

• The implementation for IQueryable<T> and its unit tests.
• How to properly test that the optimization from System\Linq\Chunk.SpeedOpt.cs is actually used.
• If the documentation is in the correct place.

[ghost]

Note regarding the new-api-needs-documentation label:

This serves as a reminder for when your PR is modifying a ref *.cs file and adding/modifying public APIs, to please make sure the API implementation in the src *.cs file is documented with triple slash comments, so the PR reviewers can sign off that change.

[ghost]

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Issue Details

---

Fix #27449

Some things I would especially like feedback on is:

• The implementation for IQueryable<T> and its unit tests.
• How to properly test that the optimization from System\Linq\Chunk.SpeedOpt.cs is actually used.
• If the documentation is in the correct place.

Author:	inputfalken
Assignees:	-
Labels:	area-System.Linq, new-api-needs-documentation
Milestone:	-

[eiriktsarpalis]

LGTM, thank you for your contribution!

[eiriktsarpalis]

Build failure

NETCORE_ENGINEERING_TELEMETRY=Build) Validation Failed: System.Drawing.Common is harvesting assets from package version 5.0.0 which is not the latest for that package release.

seems unrelated to the change, merging away.