Fix form custom fields

[mtruj013]

Done

• Fix custom fields not being passed through on submission

QA

• View the site locally in your web browser at: https://ubuntu-com-13248.demos.haus/landscape/pricing
• Click on "Get Landscape SaaS" CTA
• Fill out and submit the form with the network tab on dev tools open
• See that the checkbox answers are included in the "Comments_from_lead_c" field

Issue / Card

Fixes #13187 , https://warthogs.atlassian.net/browse/WD-6566

Screenshots

[webteam-app]

Demo starting at https://ubuntu-com-13248.demos.haus

[codecov]

Codecov Report

Merging #13248 (e463af9) into main (c2736db) will not change coverage.
Report is 4 commits behind head on main.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main   #13248   +/-   ##
=======================================
  Coverage   75.31%   75.31%           
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  Files         106      106           
  Lines        2840     2840           
  Branches      929      929           
=======================================
  Hits         2139     2139           
  Misses        679      679           
  Partials       22       22           

[steverydz]

LGTM 👍