Adds license header to assignments.js

Signed-off-by: Konstantina Blazhukova <[email protected]>

test/solidity/assignments/assignments.js

@@ -1,3 +1,23 @@
+/*-
+ *
+ * Hedera Smart Contracts
+ *
+ * Copyright (C) 2023 Hedera Hashgraph, LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
 const { expect } = require('chai')
 const { ethers } = require('hardhat')
 const Constants = require('../../constants')