feat(eslint/jsx_a11y): implement anchor_ambiguous_text

[jelly]

There is a remaining clippy issue with passing COW<_, str> which I simply can't resolve, but maybe there is more to fix first in my approach.

Currently this PR might do a bit too much allocations:

• trim() - this sadly has no cowutils replacement but might not be needed. I kept the trim() in there as a "maybe optimisation" to skip the whole string modification shenanigans
• replace() can't be used so I used retain (which also is a bit faster iirc?), but that converts COW => String. So maybe this should chain cow_replace?
• I'm also not sure if if normalized_str.contains(char::is_whitespace) { is worth it? But my gut feeling is that it is, as it deconstructs and constructs a whole String<>

[codspeed-hq]

CodSpeed Performance Report

Merging #5729 will not alter performance

_{Comparing jelly:anchor_ambiguous_text (7b3c919) with main (e26916c)}

Summary

✅ 30 untouched benchmarks

[Boshen]

@camc314 can you help and get this PR merged.

[camc314]

thank you!