Remove Facebook from footer

[xmatthewx]

Mozilla is no longer active on Facebook b/c of recent events. We should remove the Facebook icon and link from the footer of our active properties. I don't think we need to stop using share on facebook buttons, people can make that choice for themselves.

cc @alanmoo to triage
cc @kristinashu for any design considerations that pop up

Footers:

• foundation site
• pulse
• donate
• mozfest

Anywhere else critical?

[alanmoo]

@mmmavis This might be a good "when you have a few minutes" ticket. Maybe just comment it out so that if we do come back it's easy to revert?

[mmmavis]

@alanmoo yea i can take this on if we do wanna remove facebook link/icon from our site footer.

[alanmoo]

Yeah do it. Just confirmed with Matthew.

[mmmavis]

It seems like Foundation site is the only site out of the 4 listed that shows Facebook on the site footer. I've filed a PR to remove it.