Remove form from AWS re:invent page + remove from featured events

Description

Remove form from AWS re:Invent page + remove AWS re:Invent from featured events

❓ Is the rest of this necessary to fill out for this request @jareko? I included the links and references for the pages in the final section.

Checklist when modifying an existing page:

• What is the goal of changing the page?
• What metrics are we trying to affect?
• How will we decide if the change was successful or not?
• Would we revert the changes if we decided that it was not a success?
• Make sure events are reflected in Google Analytics/Marketo if the page is changed
• Make sure redirection is done if we change the page so email newsletters do not contain dead link

Proposal

Links / references

• Landing page to remove form: https://about.gitlab.com/events/aws-reinvent/
• /events/ for featured events request: https://about.gitlab.com/events/