fix: disable bench auto-discovery to exclude fixtures from CodSpeed

Since edition 2018+, Cargo auto-discovers all `benches/*.rs` files as
benchmark targets regardless of explicit `[[bench]]` entries.
`benches/fixtures.rs` is a shared data module (not a runnable benchmark),
so it gets picked up without `harness = false`, causing CodSpeed to
reject it.

Setting `autobenches = false` in `[package]` disables auto-discovery
so only the explicitly declared `[[bench]]` targets are used.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: Brooooooklyn

Cargo.toml

@@ -6,6 +6,7 @@ repository = "https://github.com/hyf0/sugar_path"
 version = "1.2.1"
 edition = "2024"
 license = "MIT"
+autobenches = false
 
 [features]
 # Enable `cached_current_dir` will make `SugarPath` to only call `std::env::current_dir` once for all path operations.