Remove TODO I am not going to do

(This is simply defined in the protocol as Scalar::ONE)

src/tests.rs

@@ -114,7 +114,7 @@ async fn test_credential_operations() {
                 scalar_u32(&cred.invites_remaining).unwrap(),
                 LEVEL_INVITATIONS[i] - j - 1
             );
-            // TODO: Where is this defined? Should I use the library constant?
+
             assert_eq!(scalar_u32(&friend_cred.trust_level).unwrap(), 1);
             assert_eq!(&cred.bucket, &friend_cred.bucket);
         }