fix(es/testing): Make test_inline! not read output as a file (#8569)

**Description:** I made a mistake while working on `test_inline!` **Related issue:** - #8568

Author: kdy1

crates/swc_ecma_transforms_testing/src/lib.rs

@@ -361,12 +361,10 @@ where
 {
  let _logger = testing::init();
 
- let expected = read_to_string(output);
- let _is_really_expected = expected.is_ok();
- let expected = expected.unwrap_or_default();
+ let expected = output;
 
  let expected_src = Tester::run(|tester| {
- let expected_module = tester.apply_transform(noop(), "expected.js", syntax, &expected)?;
+ let expected_module = tester.apply_transform(noop(), "expected.js", syntax, expected)?;
 
  let expected_src = tester.print(&expected_module, &Default::default());
 
@@ -411,8 +409,8 @@ where
 
  Ok(actual_src)
  })
- .1
- .to_string();
+ .0
+ .unwrap();
 
  assert_eq!(
  expected_src, actual_src,