support C++23 character range formatting #3857
Description
In C++23 it's possible to use the s formatter to format char ranges as strings
| Format String | Contents | Formatted Output |
|---|---|---|
| {:s} | vector{'H', '\t', 'l', 'l', 'o'} | H llo |
| {:?s} | vector{'H', '\t', 'l', 'l', 'o'} | "H\tllo" |
Trying to do the same with libfmt results in an "invalid format specifier" error