Update test input

Author: kevinweber

packages/react-refresh/src/__tests__/ReactFreshBabelPlugin-test.js

@@ -504,10 +504,15 @@ describe('ReactFreshBabelPlugin', () => {
   it("respects Babel's envName option", () => {
     const envName = 'random';
     expect(() =>
-      transform(`export default function BabelEnv () { return null };`, {
-        envName,
-        skipEnvCheck: false,
-      }),
+      transform(
+        `export default function Foo() {
+          return <h1>Hi</h1>;
+        }`,
+        {
+          envName,
+          skipEnvCheck: false,
+        },
+      ),
     ).toThrowError(
       'React Refresh Babel transform should only be enabled in development environment. ' +
         'Instead, the environment is: "' +