Agreement docs: Eliminate redundant nested peer_public_key in example.

src/agreement.rs

@@ -32,18 +32,18 @@
 //! // message.
 //! let my_public_key = my_private_key.compute_public_key()?;
 //!
-//! let peer_public_key = {
+//! let peer_public_key_bytes = {
 //!     // In a real application, the peer public key would be parsed out of a
 //!     // protocol message. Here we just generate one.
-//!     let peer_public_key = {
-//!         let peer_private_key =
-//!             agreement::EphemeralPrivateKey::generate(&agreement::X25519, &rng)?;
-//!         peer_private_key.compute_public_key()?
-//!     };
-//!
-//!     agreement::UnparsedPublicKey::new(&agreement::X25519, peer_public_key)
+//!     let peer_private_key =
+//!         agreement::EphemeralPrivateKey::generate(&agreement::X25519, &rng)?;
+//!     peer_private_key.compute_public_key()?
 //! };
 //!
+//! let peer_public_key = agreement::UnparsedPublicKey::new(
+//!     &agreement::X25519,
+//!     peer_public_key_bytes);
+//!
 //! agreement::agree_ephemeral(
 //!     my_private_key,
 //!     &peer_public_key,