Missing reference to unsupported connectors in general limitations.

[marcadamcarter]

Adding this under "Dataflows in Premium" heading might make more sense if there were a matching subheading in that section.

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

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[Jak-MS]

@davidiseminger

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label:"aq-pr-triaged"

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[davidiseminger]

Good addition - thanks.