message: Fix help message in features.rs test
diff: @@ -1939,7 +1939,8 @@ fn virtual_ws_flags() {
  p.cargo("build --features=f1")
  .with_stderr(
  "[ERROR] --features is not allowed in the root of a virtual workspace\n\
  - note: while this was previously accepted, it didn't actually do anything",
  + [NOTE] while this was previously accepted, it didn't actually do anything\n\
  + [HELP] change the current directory to the package directory, or use the --manifest-path flag to the path of the package",
  )
  .with_status(101)
  .run();
  @@ -1947,7 +1948,8 @@ fn virtual_ws_flags() {
  p.cargo("build --no-default-features")
  .with_stderr(
  "[ERROR] --no-default-features is not allowed in the root of a virtual workspace\n\
  - note: while this was previously accepted, it didn't actually do anything",
  + [NOTE] while this was previously accepted, it didn't actually do anything\n\
  + [HELP] change the current directory to the package directory, or use the --manifest-path flag to the path of the package",
  )
  .with_status(101)
  .run();
  