[epic] Set up 11ty site for brand.redhat.com

[markcaron]

Set up an 11ty site that uses the current design for ux.redhat.com, but is a structural copy of the current brand.redhat.com.

This will be an intermediary step to get Brand dot off Drupal and onto the same tooling/framework as our other design documentation sites, and toward the eventual step of a shared architecture between the sites.

• Import Maps and RHDS dependencies #5
• Deploy preview URLS should include PR # #6
• Video embed #7
• rhb-card equal height #13
• Rel noreferrer links on target blank #14

[bennypowers]

from standup today: Port over content an minimal templates from brand-dot to a new 11ty site based loosely on ux-dot's 11ty config. DON'T include the ux-dot sass or nunjucks components, pending retooling to webc

for reference, here's an implementation of secondary nav for nunjucks (warts and all) which we can use when initially porting over the brand-dot templates