message: Make preview test pass
diff: @@ -5,6 +5,7 @@ pub mod utils;
  use assert_cmd::prelude::*;
  +use std::env;
  use std::fs::File;
  use std::io::Write;
  use std::process::Command;
  @@ -50,7 +51,6 @@ fn it_can_preview_webpack_project() {
  utils::create_temporary_copy(fixture);
  settings! {fixture, r#"
  type = "webpack"
  - webpack_config = "webpack.config.js"
  "#};
  preview(fixture);
  utils::cleanup(fixture);
  @@ -70,7 +70,7 @@ fn it_can_preview_rust_project() {
  fn preview(fixture: &str) {
  // Lock to avoid having concurrent builds
  let _g = BUILD_LOCK.lock().unwrap();
  -
  + env::remove_var("CF_ACCOUNT_ID");
  let mut preview = Command::cargo_bin(env!("CARGO_PKG_NAME")).unwrap();
  preview.current_dir(utils::fixture_path(fixture));
  preview.arg("preview").arg("--headless").assert().success();
  