docs(material/datepicker): fix incorrect provideLuxonDateAdapter usage for UTC

The docs incorrectly showed provideLuxonDateAdapter accepting a second
options parameter for useUtc configuration. Unlike provideMomentDateAdapter,
the Luxon adapter provider function only accepts a formats parameter.
The correct way to configure UTC parsing is by providing the
MAT_LUXON_DATE_ADAPTER_OPTIONS injection token separately.

Fixes #32935

Author: yogeshwaran-c