wycheproof2blb: fix blobby import (#1219)

Author: kpp

wycheproof2blb/Cargo.toml

@@ -11,7 +11,7 @@ edition = "2024"
 rust-version = "1.85"
 
 [dependencies]
-blobby = { version = "0.4.0-pre", path = "../blobby" }
+blobby = { version = "0.4.0-pre", path = "../blobby", features = ["alloc"] }
 hex = "0.4"
 serde = { version = "1.0.184", features = ["derive"] }
 serde_json = "1"