Rollup merge of #120439 - seqre-contrib:moving-ui-tests, r=nnethercote

Move UI issue tests to subdirectories

I've moved issue tests numbered 1920, 3668, 5997, 23302, 32122, 40510, 57741, 71676, and 76077 to relevant better-named subdirectories (tracking issue #73494). The issues were chosen by having the highest number of files per issue.

I adjusted the `ISSUES_ENTRY_LIMIT` because `tidy` was shouting at me.

Author: GuillaumeGomez