Update style guide to discourage use of hyperlinks in headings

[nate-double-u]

Update Headings and titles section of the style guide to specifically discourage the use of hyperlinks in headings.

This topic came up in discussion around a blog article:

About hyperlinks in headings: having them makes the site slightly harder to maintain. We may one day want to make a change that means we first need to clean up all the headings that contain hyperlinks.

How likely is this change going to happen? Asking because I really like the idea (as I see value in it) of giving readers easy access to KEP links without venturing in the entire paragraph.

Hyperlinks in headings are rare in the Kubernetes blog (and even rarer in the documentation). Even though links in headers are not explicitly discouraged in the style guide, this can be considered an unwritten rule (Let's consider it written since Tim brought it up?). I don't recommend the practice either if for no other reason than headings become links, and having links in links gets hard to manage. If you need to link something and find the only place to do it is in a header, it's best to rewrite that paragraph to better support what you want to communicate.

Edit: I don't know how screen readers would manage links in headers either, so accessibility tools are another argument against this.

Originally posted by @nate-double-u in #48585 (comment)

[dipesh-rawat]

/language en
/triage accepted