AMP Carousel 0.2 (and 0.1) showing 1 pixel of previous slide in type=slides

## What's the issue?

We're using amp-carousel and have been noticing that in some brower viewport sizes that a portion of the previous slide image is displaying within the visible slide container.

I created a GIF detailing the experience at https://cl.ly/8ee465be9fcb using the iOS simulator tool and our designer submitted a screenshot https://cl.ly/f845a564e11c.

## How do we reproduce the issue?

An example can be found at https://cdpn.io/conwaydev/debug/1ead27c133f85bb192a2f3ab9a011f96#development=1 (and code at https://codepen.io/conwaydev/pen/1ead27c133f85bb192a2f3ab9a011f96?editors=1000). Its not super consistent but I can reproduce when resizing my browser.

## What browsers are affected?

All browsers

## Which AMP version is affected?

AMP ⚡ HTML – Version 1909181902540

Start with the linked CodePen reproduction and the amp-carousel implementation for type=slides; resize the viewport across the affected browser sizes and compare the visible slide boundary. Done means the previous slide is fully hidden at every viewport size described by the reproduction.

Written by the indexing model from the issue text.