Removed gif from README (WordPress#18200)

I've removed the gif from the readme file for now. While making a gif, I've run into some quality issues, so just holding off until I get it right.

Author: mapk

README.md

@@ -32,7 +32,6 @@ Here's why we're looking at the whole editing screen, as opposed to just the con
 4. **A fresh look at content creation.** Considering the whole interface lays a solid foundation for the next focus: full site customization.
 5. **Modern tooling.** Looking at the full editor screen also gives WordPress the opportunity to drastically modernize the foundation, and take steps towards a more fluid and JavaScript-powered future that fully leverages the WordPress REST API.
 
-![Editing layout in Gutenberg 6.8](https://cldup.com/HDcDkFoTik.gif)
 
 ## Blocks