vendors/execa.js/checkPathExt
    function checkPathExt(path3, options) {
      var pathext = options.pathExt !== void 0 ? options.pathExt : process.env.PATHEXT;
      if (!pathext) {
        return true;
      }
      pathext = pathext.split(";");
      if (pathext.indexOf("") !== -1) {
        return true;
      }
      for (var i = 0; i < pathext.length; i++) {
        var p = pathext[i].toLowerCase();
        if (p && path3.substr(-p.length).toLowerCase() === p) {
          return true;
        }
      }
      return false;
    }