Fix typo

     * 

     * When the parameter passed to `hasOutput` is a string, the verification succeeds iff

     * this string is the first and only line of output of the command.

     * When the praameter passed to `hasOutput` is a list, the verification succeeds iff

     * When the parameter passed to `hasOutput` is a list, the verification succeeds iff

     * the output lines are exactly the ones in the list.

     * 

     * @param {string} command A command to execute