fix(VCard): hide progress border in forced-colors mode

[06b]

Description

fixes #21835

Markup:

<template>
  <v-row dense>
    <v-col v-for="(variant, i) in variants" :key="i" cols="12" md="4">
      <v-card
        :variant="variant"
        class="mx-auto"
        color="surface-variant"
        max-width="344"
        subtitle="Greyhound divisely hello coldly fonwderfully"
        title="Headline"
      >
        <template v-slot:actions>
          <v-btn text="Button"></v-btn>
        </template>
      </v-card>

      <div class="text-center text-caption">{{ variant }}</div>
    </v-col>
  </v-row>
  <v-row dense>
    <v-col v-for="(variant, i) in variants" :key="i" cols="12" md="4">
      <v-card
        :variant="variant"
        class="mx-auto"
        color="surface-variant"
        max-width="344"
        subtitle="Greyhound divisely hello coldly fonwderfully"
        title="Headline (Loading)"
        loading
      >
        <template v-slot:actions>
          <v-btn text="Button"></v-btn>
        </template>
      </v-card>

      <div class="text-center text-caption">{{ variant }}</div>
    </v-col>
  </v-row>
</template>

<script>
  export default {
    data: () => ({
      variants: ['elevated', 'flat', 'tonal', 'outlined', 'text', 'plain'],
    }),
  }
</script>

negative