Adding copyright header to generated test file (#351)

src/tests/full_test.rs

@@ -782,9 +782,18 @@ fn generate_test_vectors() -> Result<(), ProtocolError> {
 
     #[rustfmt::skip]
     output.push_str(
-        "// To regenerate these test vectors, run:\n\
-         // FULL_TEST_VECTORS_FILE=src/tests/full_test_vectors.rs cargo test --features ristretto255,curve25519 -- generate_test_vectors\n\
-         \n",
+        "\
+        // Copyright (c) Meta Platforms, Inc. and affiliates.\n\
+        //\n\
+        // This source code is dual-licensed under either the MIT license found in the\n\
+        // LICENSE-MIT file in the root directory of this source tree or the Apache\n\
+        // License, Version 2.0 found in the LICENSE-APACHE file in the root directory\n\
+        // of this source tree. You may select, at your option, one of the above-listed\n\
+        // licenses.\n\
+        //\n\
+        // To regenerate these test vectors, run:\n\
+        // FULL_TEST_VECTORS_FILE=src/tests/full_test_vectors.rs cargo test --features ristretto255,curve25519 -- generate_test_vectors\n\
+        \n",
     );
 
     #[cfg(feature = "ristretto255")]