README.md: Add link to Homebrew blog

Inspired by https://github.com/Homebrew/brew/issues/8096 and https://github.com/Homebrew/brew/pull/8098

. I think the blog is an important way for regular users to keep up-to-date with Homebrew evolution, so it deserves an entry in the main docs page.

Update docs/README.md

Co-authored-by: Mike McQuaid <mike@mikemcquaid.com>

docs/README.md

@@ -3,6 +3,7 @@
 ## Users
 
 - [`brew` man-page (command documentation)](Manpage.md)
+- [Homebrew Blog (news on major updates)](https://brew.sh/blog/)
 - [Troubleshooting](Troubleshooting.md)
 - [Installation](Installation.md)
 - [Frequently Asked Questions](FAQ.md)