Update kdtree requirement from 0.7.0 to 0.8.0

Updates the requirements on [kdtree](https://github.com/mrhooray/kdtree-rs) to permit the latest version.
- [Changelog](https://github.com/mrhooray/kdtree-rs/blob/master/release.toml)
- [Commits](mrhooray/kdtree-rs@v0.7.0...v0.8.0)

---
updated-dependencies:
- dependency-name: kdtree
  dependency-version: 0.8.0
  dependency-type: direct:production
...

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

Author: dependabot[bot]

algorithms/linfa-nn/Cargo.toml

@@ -31,7 +31,7 @@ noisy_float = "0.2.0"
 order-stat = "0.1.3"
 thiserror = "2.0"
 
-kdtree = "0.7.0"
+kdtree = "0.8.0"
 
 linfa = { version = "0.8.0", path = "../.." }