[Bug Report][2.5.3] v-tabs-slider incorrect width on initial render

[davidbielik]

Environment

Vuetify Version: 2.5.3
Vue Version: 2.6.13
Browsers: Chrome 90.0.4430.212
OS: Mac OS 10.15.7

Steps to reproduce

1. Hard Refresh (CMD+SHIFT+R)
2. Look at the active v-tabs-slider

Expected Behavior

slider should not exceed the width of the tab

Actual Behavior

slider exceeds the width of the tab

Reproduction Link

https://codepen.io/codepen123456789/pen/XWMZPON

Other comments

switching between tabs to re-render it, causes it to resume the correct width. the initial rendering seems to be incorrect based on how quickly the tab contents/icon loads

[jacekkarczmarczyk]

Duplicate of #4733