Remove hashbrown dependency

Author: nyxtom

Cargo.toml

@@ -50,7 +50,6 @@ serde = "1.0.117"
 serde_json = "1.0.59"
 routefinder = "0.5.0"
 regex = "1.5.5"
-hashbrown = "0.12.3"
 
 [dev-dependencies]
 async-std = { version = "1.6.5", features = ["unstable", "attributes"] }