feat(VItemGroup): add tag prop to component

[ElijahKotyluk]

Description

resolves #11392

Motivation and Context

How Has This Been Tested?

Jest | playground

Markup:

<template>
  <v-item-group tag="footer">
    <v-container>
      <v-row>
        <v-col
          v-for="n in 3"
          :key="n"
          cols="12"
          md="4"
        >
          <v-item v-slot="{ active, toggle }">
            <v-card
              :color="active ? 'primary' : ''"
              class="d-flex align-center"
              dark
              height="200"
              @click="toggle"
            >
              <v-scroll-y-transition>
                <div
                  v-if="active"
                  class="display-3 flex-grow-1 text-center"
                >
                  Active
                </div>
              </v-scroll-y-transition>
            </v-card>
          </v-item>
        </v-col>
      </v-row>
    </v-container>
  </v-item-group>
</template>

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Improvement/refactoring (non-breaking change that doesn't add any features but makes things better)

Checklist:

• The PR title is no longer than 64 characters.
• The PR is submitted to the correct branch (master for bug fixes and documentation updates, dev for new features and backwards compatible changes and next for non-backwards compatible changes).
• My code follows the code style of this project.
• I've added relevant changes to the documentation (applies to new features and breaking changes in core library)

[jacekkarczmarczyk]

tag may be misleading - it suggest that it's the tag for component itself, not for the item, maybe item-tag would be better?

Also please provide playground for your PRs. Thanks

[KaelWD]

it suggest that it's the tag for component itself, not for the item

It is for the component though?

[jacekkarczmarczyk]

It is for the component though?

Ah yeah, i guess i was mislead by some other playground or other piece of code