message: Don't pass --open as an argument.
diff: @@ -1505,7 +1505,7 @@ fn doc_workspace_open_different_library_and_package_names() {
  // The order in which bar is compiled or documented is not deterministic
  assert_that(
  - p.cargo("doc").arg("--open").env("BROWSER", "echo"),
  + p.cargo("doc --open").env("BROWSER", "echo"),
  execs()
  .with_status(0)
  .with_stderr_contains("[..] Documenting foo v0.1.0 ([..])")
  