Update dashmap requirement from 5.1 to 6.0 (#162)

Updates the requirements on [dashmap](https://github.com/xacrimon/dashmap) to permit the latest version.
- [Release notes](https://github.com/xacrimon/dashmap/releases)
- [Commits](xacrimon/dashmap@v5.1.0...v6.0.0)

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

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

Author: dependabot[bot]

Cargo.toml

@@ -30,7 +30,7 @@ async-trait = "0.1"
 bytes = "1.2"
 cbc = {version = "0.1", features = ["std"], optional = true}
 chrono = {version = "0.4", default-features = false, features = ["clock", "std", "serde"], optional = true}
-dashmap = {version = "5.1", optional = true}
+dashmap = {version = "6.0", optional = true}
 futures = "0.3"
 futures-util = "0.3"
 jsonwebtoken = {version = "9.0", optional = true}