[FEAT] - Capture - Add page.screenshot API options to BackstopJS-configuration options

[dgrebb]

Summary

Problem

Reducing motion is a very necessary challenge when taking screen shots. The Playwright screenshot API has a parameter, animation, that could be used to achieve faster capture.

Page-level APIs aren't currently exposed, so this cannot currently be added by Backstop configuration.

Solution

Add a configuration API for page-level function params that can be processed and passed into the Puppeteer and Playwright runners.

Notes

• Playwright screenshot API
• API documentation for the page.emulateMedia argument that doesn't ever seem to work
• API docuementation for the colorScheme argument that also never seems to work
• Feature Request: Playwright engine - disable animations option garris/BackstopJS#1461