message: Add test for `GIT_COMMITTER_EMAIL` when `cargo new`
  There was no test for `GIT_COMMITER_EMAIL`, so I add the test for
  this. In addition, I update the name of some tests.
diff: @@ -287,7 +287,7 @@ fn finds_local_author_git() {
  }
  #[cargo_test]
  -fn finds_git_email() {
  +fn finds_git_author() {
  cargo_process("new foo")
  .env("GIT_AUTHOR_NAME", "foo")
  .env("GIT_AUTHOR_EMAIL", "gitfoo")
  @@ -303,11 +303,12 @@ fn finds_git_email() {
  }
  #[cargo_test]
  -fn finds_git_author() {
  +fn finds_git_committer() {
  create_empty_gitconfig();
  cargo_process("new foo")
  .env_remove("USER")
  - .env("GIT_COMMITTER_NAME", "gitfoo")
  + .env("GIT_COMMITTER_NAME", "foo")
  + .env("GIT_COMMITTER_EMAIL", "gitfoo")
  .run();
  let toml = paths::root().join("foo/Cargo.toml");
  @@ -316,7 +317,7 @@ fn finds_git_author() {
  .unwrap()
  .read_to_string(&mut contents)
  .unwrap();
  - assert!(contents.contains(r#"authors = ["gitfoo"]"#));
  + assert!(contents.contains(r#"authors = ["foo <gitfoo>"]"#));
  }
  #[cargo_test]
  