error: couldn't read `$DIR/tests/ui/fail_missing_sidecar.v0.1.0.spec.md`: No such file or directory (os error 2)
 --> tests/ui/fail_missing_sidecar.rs:3:1
  |
3 | #[spec("fail_missing_sidecar.v0.1.0.spec.md")]
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^