docs(VDatePicker): hide display-value from props list

[J-Sek]

Description

display-value does not affect VDatePicker and should not appear in API docs to avoid confusion

resolves #20863

[KaelWD]

v2 had the ability to display a different date as "today" that seems to be missing in v3: https://v2.vuetifyjs.com/en/components/date-pickers/#show-current

[J-Sek]

Not sure if show-current is even in the same ballpark. The issue touches more on picker-date in v2 that got split into two props but might surprise people that expect 2-way binding to work. Personally I don't find it big of a problem at the moment and would opt for keeping the current behavior while making sure API docs are tidy.