Fix issue stellar#1405: Update test.rs to see the expected output whe…

…n running 'cargo test' in this tutorial https://developers.stellar.org/docs/build/smart-contracts/getting-started/hello-world

soroban-hello-world/contracts/hello-world/src/test.rs

@@ -0,0 +1,21 @@
+#![cfg(test)]
+
+use super::*;
+use soroban_sdk::{vec, Env, String};
+
+#[test]
+fn test() {
+    let env = Env::default();
+    let contract_id = env.register_contract(None, Contract);
+    let client = ContractClient::new(&env, &contract_id);
+
+    let words = client.hello(&String::from_str(&env, "Dev"));
+    assert_eq!(
+        words,
+        vec![
+            &env,
+            String::from_str(&env, "Hello"),
+            String::from_str(&env, "Dev"),
+        ]
+    );
+}