[n7studios]

Summary

Updates the WordPress.org readme to improve search rankings for target keywords (email subscribers, email newsletter, email marketing, landing page, membership), without keyword stuffing:

• Title, tags and short description lead with "email subscribers", the primary keyword
• Additional natural mentions of email subscribers, landing pages and email marketing in the description and FAQs
• New FAQs covering email marketing for WordPress, and combining membership sites with newsletters and the Form Builder block
• Grammar fixes e.g. "email subscriber list"

Changelog unchanged.

Checklist

• I have written a test and included it in this PR
• I have run all tests and they pass
• The code passes when running the PHP CodeSniffer
• Code meets WordPress Coding Standards for PHP, HTML, CSS and JS
• Security and Sanitization requirements have been followed
• I have assigned a reviewer or two to review this PR (if you're not sure who to assign, we can do this step for you)