fix(VDatePicker): show correct week number for selected locale

[simon-tackstrand]

Description

Current getWeek implementation does not work for different locales.
Uses @date-io adapter to calculate week number.

resolves #20490, #20724

Requires @date-io version >= 3.2.0 for any project referencing vuetify

The previous getWeek implementation has been moved to the VuetifyDateAdapter, meaning the bug will still exist for those not using any @date-io implementation.

Markup:

<template>
  <v-app>
    <v-container>
      <v-row>
        <v-col cols="12">
          <div style="height: 600px">
            <v-locale-provider locale="sv">
              <v-date-picker show-week />
            </v-locale-provider>
          </div>
        </v-col>
      </v-row>
    </v-container>
  </v-app>
</template>

<script>
  export default {
    name: 'Playground',
    setup () {
      return {
        //
      }
    },
  }
</script>