Make minor updates

[sonmarcho]

This PR introduces a minor change which is worth mentioning by updating the formatting of body regions in Charon-ML. Instead of displaying, e.g., &'0 ..., we display &°0 .... I'm not super happy with the use of the symbol ° and it can be changed: the only important thing is that I need to use a different symbol for the bound regions and for the body regions, otherwise the logs can be quite confusing when debugging.

ci: use AeneasVerif/eurydice#367
ci: use AeneasVerif/aeneas#691

[Nadrieril]

FYI they were already different: '_42 is an anonymous bound region whereas '42 is a body region (the idea being that _42 is a valid rust identifier but 42 isn't). Did you not notice or was that not clear enough still?

[sonmarcho]

FYI they were already different: '_42 is an anonymous bound region whereas '42 is a body region (the idea being that _42 is a valid rust identifier but 42 isn't). Did you not notice or was that not clear enough still?

I see, thanks for this! I found the issue in a case where there were only body regions and it was unclear to me whether they were body regions or anonymous regions. Had there been both in the context I would probably have noticed the difference. I'm still in favour of having a more discriminative formatting.