Update 7.0 migration guidance

[guardrex]

Fixes #34143

Thanks @dougclutter! 🚀

... and I missed enabling a section on @bind:get/@bind:set modifiers for binding. It was commented out at the time because there was a bug in the framework at release. The bug was fixed in a patch later. I enabled the new content in the 7.0 version of the binding article when the patch landed, but I failed to enable it in this article.

This type of mistake likely won't happen again because now I use an approach to track content that I need to address during release. I place an HTML comment into the markdown to flag items like this. In this case, I would've placed something like "UPDATE 7.0 - Enable this when patched" with the product unit issue link in the comment. Then, this comment (and all of the other 7.0 items to address in articles) for the 7.0 release come up in a simple repo search of "UPDATE 7.0". I don't close out my main release tracking issue until all of the "UPDATE {VERSION}" items have been removed from the repo markdown. That's what I do these days, and it's been working very well for the last couple of releases.

Thanks again for the issue!

---

Internal previews

📄 File	🔗 Preview link
aspnetcore/migration/60-70.md	aspnetcore/migration/60-70