Auto merge of #120227 - nnethercote:further-improve-space_between, r=petrochenkov

Further improve `space_between`

`space_between` is used by `print_tts` to decide when spaces should be put between  tokens. This PR improves it in two ways:
- avoid unnecessary spaces before semicolons, and
- don't omit some necessary spaces before/after some punctuation symbols.

r? `@petrochenkov`

Author: bors