Added missing 'serde' feature

ipp/Cargo.toml

@@ -19,7 +19,7 @@ enum-primitive-derive = "0.3"
 futures-executor = { version = "0.3", optional = true }
 log = "0.4"
 num-traits = "0.2"
-bytes = { version = "1", features = ["serde"] }
+bytes = "1"
 thiserror = "1"
 http = "1"
 serde = { version = "1", optional = true, features = ["derive"] }
@@ -49,6 +49,7 @@ tokio = { version = "1", features = ["macros", "rt-multi-thread"] }
 
 [features]
 default = ["async-client", "client", "async-client-tls", "client-tls"]
+serde = ["dep:serde", "bytes/serde"]
 async = ["futures-util", "futures-executor"]
 async-client = ["async", "reqwest", "tokio-util", "base64"]
 client = ["ureq", "base64"]