fix(VBtn): adjust large button sizes to be consistent

[kevinmarrec]

Description

Change large and x-large button sizes from 54px & 70px to 44px & 56px

Motivation and Context

See #7535

How Has This Been Tested?

Visually

Markup:

<div id="app">
  <v-app>
    <v-container fluid justify-center align-center>
      <v-btn x-small color="primary" dark>x-small</v-btn>
      <v-btn small color="secondary" dark>small</v-btn>
      <v-btn color="primary" dark>default</v-btn>
      <v-btn large color="secondary" dark>large</v-btn>
      <v-btn x-large color="primary" dark>x-large</v-btn>
    </v-container>
  </v-app>
</div>

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.

[codecov]

Codecov Report

Merging #7536 into next will decrease coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             next    #7536      +/-   ##
==========================================
- Coverage   87.11%   87.09%   -0.02%     
==========================================
  Files         325      325              
  Lines        8449     8449              
  Branches     2116     2116              
==========================================
- Hits         7360     7359       -1     
- Misses        999     1000       +1     
  Partials       90       90

Impacted Files	Coverage Δ
packages/vuetify/src/components/VSelect/VSelect.ts	93.99% <0%> (-0.43%)	⬇️

---

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[MajesticPotatoe]

Yay for normal sizes 👍

[codecov]

Codecov Report

Merging #7536 into next will increase coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             next    #7536      +/-   ##
==========================================
+ Coverage   87.09%   87.11%   +0.01%     
==========================================
  Files         325      325              
  Lines        8449     8449              
  Branches     2116     2116              
==========================================
+ Hits         7359     7360       +1     
+ Misses       1000      999       -1     
  Partials       90       90

Impacted Files	Coverage Δ
packages/vuetify/src/components/VSelect/VSelect.ts	94.42% <0%> (+0.42%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update be78722...a08b7c7. Read the comment docs.