deps: update statrs requirement from 0.16 to 0.18

Updates the requirements on [statrs](https://github.com/statrs-dev/statrs) to permit the latest version.
- [Release notes](https://github.com/statrs-dev/statrs/releases)
- [Changelog](https://github.com/statrs-dev/statrs/blob/master/CHANGELOG.md)
- [Commits](statrs-dev/statrs@0.16.0...v0.18.0)

---
updated-dependencies:
- dependency-name: statrs
  dependency-version: 0.18.0
  dependency-type: direct:production
...

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

Author: dependabot[bot]

Cargo.lock

@@ -12,4 +12,4 @@ compact_str = "0.8"
 tracing = "0.1"
 tokio = { version = "1.35", features = ["full"] }
 serde = { version = "1.0", features = ["derive"] }
-statrs = "0.16"
+statrs = "0.18"

crates/risk/Cargo.toml

@@ -15,7 +15,7 @@ serde = { workspace = true, optional = false }
 serde_json = { workspace = true, optional = false }
 tracing = { workspace = true, optional = false }
 chrono = { workspace = true, optional = false }
-statrs = "0.16"
+statrs = "0.18"
 
 [dev-dependencies]
 tokio-test = "0.4"