chore: migrate Envelope impl serialize function back to concat_ext and fixed Cargo.toml invalid inline table

Cargo.toml

@@ -68,12 +68,9 @@ serde = { version = "1", default-features = false, features = [
     "derive",
 ], optional = true }
 subtle = { version = "2.6", default-features = false }
-voprf = {
-    package = "voprf-vx",
-    version = "1.0.0-pre.0",
-    default-features = false,
-    features = ["danger"]
-}
+voprf = { package = "voprf-vx", version = "1.0.0-pre.0", default-features = false, features = [
+    "danger",
+] }
 zeroize = { version = "1.9", features = ["zeroize_derive"] }
 
 [target.'cfg(target_arch = "wasm32")'.dependencies]

src/envelope.rs

@@ -24,7 +24,7 @@ use crate::key_exchange::SerializedIdentifiers;
 use crate::key_exchange::group::Group;
 use crate::keypair::{KeyPair, PrivateKey, PublicKey};
 use crate::opaque::Identifiers;
-use crate::serialization::{SliceExt, UpdateExt};
+use crate::serialization::{GenericArrayExt, SliceExt, UpdateExt};
 
 // Constant string used as salt for HKDF computation
 const STR_AUTH_KEY: [u8; 7] = *b"AuthKey";
@@ -260,16 +260,9 @@ impl<CS: CipherSuite> Envelope<CS> {
         OutputSize::<OprfHash<CS>>::USIZE + NonceLen::USIZE
     }
 
-    // TODO: check if ok
     pub(crate) fn serialize(&self) -> GenericArray<u8, EnvelopeLen<CS>> {
-        use generic_array::typenum::Unsigned;
-
-        let mut buf = GenericArray::<u8, EnvelopeLen<CS>>::default();
-
-        buf[..NonceLen::USIZE].copy_from_slice(&self.nonce);
-        buf[NonceLen::USIZE..].copy_from_slice(&self.hmac);
-
-        buf
+        self.nonce
+            .concat_ext(&GenericArray::from_ha0_4(self.hmac.clone()))
     }
 
     pub(crate) fn deserialize_take(bytes: &mut &[u8]) -> Result<Self, ProtocolError> {