Update infrastructure-guide.md

Improve the CF website intro

infrastructure-guide.md

@@ -7,11 +7,10 @@ and standardized region list.
 
 ## CF Website
 
-The [CF Website](http://cfconventions.org) is served by GitHub Pages
-from source documents (in Markdown mainly) on the `master` branch
+The [CF Website](https://cfconventions.org) is served by [GitHub Pages](https://pages.github.com/) as static site generated by [Jekyll](https://jekyllrb.com/), and rendered from source files in [Markdown](https://github.github.com/gfm/) (mainly) on the `main` branch
 of the [CF Website repo](https://github.com/cf-convention/cf-convention.github.io).
-The CF Website pages are regenerated automatically by GitHub Pages
-whenever a commit is made to the `master` branch.
+
+The CF Website site pages are regenerated automatically by [GitHub Action](https://docs.github.com/en/actions) whenever a commit is made to the `main` branch.
 
 ### PR Testing for the CF Website
 
@@ -103,4 +102,4 @@ The process generates the KWIC Index as an HTML file.
 
 ??
 
-[cf-discuss]: https://github.com/cf-convention/discuss
+[cf-discuss]: https://github.com/cf-convention/discuss