Reduce futures-util features

Author: paolobarbolini

Cargo.toml

@@ -19,7 +19,7 @@ futures-channel = { version = "0.3.17", default-features = false, features = [
   "sink",
 ], optional = true }
 futures-util = { version = "0.3.17", default-features = false, features = [
-  "std",
+  "alloc",
   "sink",
 ] }
 tokio-postgres = { version = "0.7.10", optional = true }