docs(drawer): Updates design guidelines for v6.

[edonehoo]

Closes #4546

[edonehoo]

IDK if this is a big deal, but I noticed that the "overlay drawer" image still pushes the page content to the side, which isn't 100% accurate. It should just overlay it, so the page content should extend to the full width of the screen, including the drawer. I couldn't figure out how to fix it in Figma, so I can coordinate with whoever else can!

[patternfly-build]

Preview: https://patternfly-org-pr-4626-site.surge.sh

[bekah-stephens]

IDK if this is a big deal, but I noticed that the "overlay drawer" image still pushes the page content to the side, which isn't 100% accurate. It should just overlay it, so the page content should extend to the full width of the screen, including the drawer. I couldn't figure out how to fix it in Figma, so I can coordinate with whoever else can!

I'm not sure the best way to fix the component itself, but did a quick fix and updated the screenshot. I would say pull in the fixed screenshot for the guidelines and then add the component problem to the audit doc.

[edonehoo]

@bekah-stephens ty! Updated and added to the audit sheet