Move the Email Preference Center

Jennifer "JJ" Cordzrequested to merge
mktgops-emailsub into master

Move the email preference center from a Marketo landing page to a page on about.gitlab.com.

Fixes the link in the /install page to drive to new landing page on about.gitlab.com
Related: https://gitlab.com/gitlab-com/marketing/general/issues/2735

Edited by Jennifer "JJ" Cordz

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