Draft: [ENG] Match the bottom blog free for 30 day CTA to our Marketing site CTA

Goal

The current free trial section on the blog does not correspond to the one we have on https://about.gitlab.com/, so I updated it using the current design and this Figma file.

What changed

• New layout for the free trial CTA Desktop
• New layout for the free trial CTA Mobile

Web app links to test:

• link for regular posts
• link for release posts
• link for specific old post pattern

Code notes:

I had to use !important sometimes on the CSS file since some base styles were already applied using it, the right way to fix that would be removing the !important from the base file but that would need a refactor.

Closes gitlab-com/marketing/digital-experience/buyer-experience#2311 (closed)