`unic-char-range` is unmaintained

All Unicode crates that are part of https://github.com/open-i18n/rust-unic are unmaintained.

## Recommended alternatives

- Since version [1.45.0](https://releases.rs/docs/1.45.0/#libraries) Rust [supports](https://github.com/rust-lang/rust/pull/72413/) using `char` with `ops::{Range, RangeFrom, RangeFull, RangeInclusive, RangeTo}` to iterate over a range of codepoints.