Documentation update: Update requests for the section on Controllers and Razor Pages

[sadukie]

In the README for this repo, I noticed 2 things:

• The link in the table of contents for "Controllers and Razor Pages" is broken. The URL should link to #what-about-controllers-and-razor-pages since the heading name looks like it changed.
• " If you want to use my ApiEndpoints library, Razor Pages, and/or Controllers you can use the last template that included them, version 7.1. " - I'm not seeing a version 7.1 tag. I had someone ask me about this, and I pointed them to the dotnet-6 tag. Should this be the v6.2.8 tag? Is there a 7.1 tag that hasn't been pushed here? Whichever it is, can the README be updated to include a link to that tag or to where people can easily download that version?