update hashbrown to 0.15.

Author: Byron

gix-index/Cargo.toml

@@ -34,7 +34,7 @@ gix-lock = { version = "^17.1.0", path = "../gix-lock" }
 gix-fs = { version = "^0.15.0", path = "../gix-fs" }
 gix-utils = { version = "^0.3.0", path = "../gix-utils" }
 
-hashbrown = "0.14.3"
+hashbrown = "0.15.4"
 fnv = "1.0.7"
 thiserror = "2.0.0"
 memmap2 = "0.9.0"