Fix a typo

[TrickyCat]

trafficstars

Fix a typo to use the correct type

[learn-build-service-prod[bot]]

Learn Build status updates of commit c28b9ce:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
docs/high-performance/Memory2D.md	:white_check_mark:Succeeded	View

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[TrickyCat]

@Sergio0694 @jfversluis

How can we merge it?

[jfversluis]

Thanks for the nudge on these @TrickyCat!