Update all documentation links to WCAG 2.2 equivalent

[lb-]

It would be good for all the links to the WCAG website be updated to the equivalent WCAG 2.2 standard.

This came out just over a year ago now and should be the canonical links we provide when giving guidance to developers.

There was this issue #1008 - however it was more about rules that need to change.

I am only suggesting we change our links in the documentation.

[ljharb]

The links in docs should match what we implement; we shouldn’t link to 2.2 unless we comply with it.

[lb-]

As per https://www.w3.org/WAI/standards-guidelines/wcag/new-in-22/#changes-from-wcag-21-to-wcag-22

WCAG 2.2 provides 9 additional success criteria since WCAG 2.1. They are introduced on this page.

The 2.0 and 2.1 success criteria are essentially the same in 2.2, with one exception: 4.1.1 Parsing is obsolete and removed from WCAG 2.2. More information is in WCAG 2 FAQ, 4.1.1 Parsing. WCAG 2.2 includes Notes about different languages; more information is in WCAG 2 FAQ, internationalization.

I have noticed that some links have better linked examples and explanations but the actual success criteria itself remains the same.

See a similar comment on the PR. #1016 (comment)