Update `/free-trial` page to new layout

In Issue gitlab-com/marketing/general#2330, we agreed directionally the first iteration of new landing page will mirror the GKE webcast.

MVC 1

• Convert Marketo form to single column - @jjcordz
• Updated /free-trial/ to new format, e.g. GKE webcast - @jareko / @luke
• Set up test to measure against original /free-trial/ page - @lbanks

MVC 2

• Update hero and body copy - copy doc - @erica / @luke

MVC 3

• Add Axway callout from copy doc - @jareko / @luke

MVC 4

• Convert page layout into template that can be easily duplicated for future webcasts, downloadable content, events, etc. - @jareko / @luke