message: test: Increase CLI test coverage under different feature sets
diff: #[test]
  #[cfg(feature = "syntax-highlight")]
  fn cli_tests() {
  - trycmd::TestCases::new().case("tests/cmd/*.md");
  + let t = trycmd::TestCases::new();
  + t.case("tests/cmd/*.md");
  + #[cfg(not(feature = "serve"))]
  + {
  + t.skip("tests/cmd/errors.md");
  + }
  }
  