Remove secret function from SecretShare (#495)

This is because we now can use the getter to get signing_share() without the need for an additional function

frost-core/src/frost/keys.rs

@@ -390,11 +390,6 @@ where
         }
     }
 
-    /// Gets the inner [`SigningShare`] value.
-    pub fn secret(&self) -> &SigningShare<C> {
-        &self.signing_share
-    }
-
     /// Verifies that a secret share is consistent with a verifiable secret sharing commitment,
     /// and returns the derived group info for the participant (their public verification share,
     /// and the group public key) if successful.

frost-core/src/tests/repairable.rs

@@ -89,7 +89,7 @@ pub fn check_rts<C: Ciphersuite, R: RngCore + CryptoRng>(mut rng: R) {
     );
 
     // TODO: assert on commitment equality as well once updates have been made to VerifiableSecretSharingCommitment
-    assert!(participant.secret() == participant_recovered_share.secret())
+    assert!(participant.signing_share() == participant_recovered_share.signing_share())
 }
 
 fn generate_scalar_from_byte_string<C: Ciphersuite>(

frost-core/src/tests/vectors.rs

@@ -213,7 +213,7 @@ pub fn check_sign_with_test_vectors<C: Ciphersuite>(json_vectors: &Value) {
         );
         assert_eq!(
             key_package.signing_share(),
-            secret_shares[key_package.identifier()].secret()
+            secret_shares[key_package.identifier()].signing_share()
         )
     }
 
@@ -225,7 +225,7 @@ pub fn check_sign_with_test_vectors<C: Ciphersuite>(json_vectors: &Value) {
         let nonces = signer_nonces.get(&i).unwrap();
 
         // compute nonces from secret and randomness
-        let secret = secret_shares[&i].secret();
+        let secret = secret_shares[&i].signing_share();
 
         let hiding_nonce_randomness = &hiding_nonces_randomness[&i];
         let hiding_nonce = Nonce::nonce_generate_from_random_bytes(