fix(VInput): attrs should be applied on input not root element

[nekosaur]

Description

this fixes issue where setting for example tabindex on checkbox
results in it being applied both in input element and on root div

Motivation and Context

closes #5412

How Has This Been Tested?

Markup:

<template>
  <v-layout row>
    <v-checkbox tabindex="0" label="asd"></v-checkbox>
  </v-layout>
</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 feature but make 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 breaking 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)

[codecov]

Codecov Report

Merging #7579 into next will decrease coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             next    #7579      +/-   ##
==========================================
- Coverage   86.94%   86.93%   -0.02%     
==========================================
  Files         326      326              
  Lines        8540     8540              
  Branches     2154     2154              
==========================================
- Hits         7425     7424       -1     
- Misses       1025     1026       +1     
  Partials       90       90

Impacted Files	Coverage Δ
packages/vuetify/src/components/VInput/VInput.ts	97.18% <ø> (ø)	⬆️
packages/vuetify/src/components/VSelect/VSelect.ts	93.04% <0%> (-0.37%)	⬇️

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