Update hashbrown requirement from 0.11.0 to 0.12.0 (#288)

Updates the requirements on [hashbrown](https://github.com/rust-lang/hashbrown) to permit the latest version.
- [Release notes](https://github.com/rust-lang/hashbrown/releases)
- [Changelog](https://github.com/rust-lang/hashbrown/blob/master/CHANGELOG.md)
- [Commits](rust-lang/hashbrown@v0.11.0...v0.12.0)

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

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

dyn-cache/Cargo.toml

@@ -20,7 +20,7 @@ wasm-bindgen = [ "parking_lot/wasm-bindgen" ]
 [dependencies]
 downcast-rs = "1.1.1"
 hash_hasher = "2.0.3"
-hashbrown = "0.11.0"
+hashbrown = "0.12.0"
 illicit = { path = "../illicit", version = "1.1.2"}
 parking_lot = "0.11.0"
 paste = "1.0.0"