Update datamarts-overview.md

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

Learn Build status updates of commit 407a0b6:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
powerbi-docs/transform-model/datamarts/datamarts-overview.md	:white_check_mark:Succeeded

For more details, please refer to the build report.

For any questions, please:

• Try searching the learn.microsoft.com contributor guides
• Post your question in the Learn support channel

[Court72]

@davidiseminger

Can you review the proposed changes?

When the changes are ready for publication, add a #sign-off comment to signal that the PR is ready for the review team to merge.

label:"aq-pr-triaged"

@MicrosoftDocs/public-repo-pr-review-team

[davidiseminger]

sign-off