Fix typo: 'how to uses' -> 'how to use'

[mvanhorn]

Fixes a typo in the dataflow block documentation.

Before: "This article shows how to uses the BufferBlock class."
After: "This article shows how to use the BufferBlock class."

Closes #52988

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Internal previews

📄 File	🔗 Preview link
docs/standard/parallel-programming/how-to-write-messages-to-and-read-messages-from-a-dataflow-block.md	docs/standard/parallel-programming/how-to-write-messages-to-and-read-messages-from-a-dataflow-block

[gewarren]

Thanks @mvanhorn

[mvanhorn]

Thanks for the quick merge, @gewarren!