chore(meta): change crates.io's category to config

Author: BobAnkh

Cargo.toml

@@ -9,7 +9,7 @@ homepage = "https://github.com/stack-rs/netem-trace"
 repository = "https://github.com/stack-rs/netem-trace"
 keywords = ["emulation", "trace", "network", "utility", "model"]
 documentation = "https://docs.rs/netem-trace"
-categories = ["network-programming", "configuration", "development-tools", "simulation"]
+categories = ["network-programming", "config", "development-tools", "simulation"]
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html