build(deps): update bitcoin_hashes requirement from 0.12 to 0.16

Updates the requirements on [bitcoin_hashes](https://github.com/rust-bitcoin/rust-bitcoin) to permit the latest version.
- [Release notes](https://github.com/rust-bitcoin/rust-bitcoin/releases)
- [Changelog](https://github.com/rust-bitcoin/rust-bitcoin/blob/master/CHANGELOG.md)
- [Commits](rust-bitcoin/rust-bitcoin@bitcoin_hashes-0.12.0...bitcoin_hashes-0.16.0)

---
updated-dependencies:
- dependency-name: bitcoin_hashes
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Cargo.toml

@@ -11,7 +11,7 @@ edition = "2021"
 repository = "https://github.com/dspicher/ur-rs/"
 
 [dependencies]
-bitcoin_hashes = { version = "0.12", default-features = false }
+bitcoin_hashes = { version = "0.16", default-features = false }
 crc = "3"
 minicbor = { version = "0.25", features = ["alloc"] }
 phf = { version = "0.11", features = ["macros"], default-features = false }