Docs: Remove Outreach doc from Getting Started section

[ndiego]

What?

This PR removes the Outreach page from the Getting Started section of the Block Editor Handbook (BEH) and moves any still relevant information to other docs. This is part of an effort to streamline the Getting Started section and provide a better developer experience.

Why?

The current Outreach page in the BEH contains very outdated information, is a maintenance burden, and is not something that should be included in the documentation. It served its purpose in the past but is no longer needed. We also have better places for much of this content, like learn.wordpress.org, the WordPress Developer Blog, and other sections of the BEH itself.

How?

Remove the Outreach page and move all relevant content to either the Getting Started or History docs.

[github-actions]

Flaky tests detected in 22a8f9a.
Some tests passed with failed attempts. The failures may not be related to this commit but are still reported for visibility. See the documentation for more information.

🔍 Workflow run URL: https://github.com/WordPress/gutenberg/actions/runs/6184735182
📝 Reported issues:

• [Flaky Test] Should load the view script if the lightbox is disabled in theme.json but enabled via block settings #53782 in /test/e2e/specs/editor/various/behaviors.spec.js