Remove unused libherokubuildpack feature

Author: schneems

Cargo.lock

@@ -10,7 +10,7 @@ workspace = true
 buildpacks-jvm-shared.workspace = true
 indoc = "2"
 libcnb = "=0.26.0"
-libherokubuildpack = { version = "=0.26.0", default-features = false, features = ["command", "error"] }
+libherokubuildpack = { version = "=0.26.0", default-features = false, features = ["error"] }
 nom = "7"
 serde = { version = "1", features = ["derive"] }
 tempfile = "3.15.0"