fix issue #4327: Outputs of code not visible in Guide

[webermayank]

Description

Fixes issue - nightwatchjs/nightwatch#4327

Fixed the issue of output not showing in Guide sections

Screenshots of Solved Issue

fixed for - https://nightwatchjs.org/guide/running-tests/catch-js-exceptions.html

• Click on link -> scroll down
  

fixed for - https://nightwatchjs.org/guide/configuration/define-test-environments.html

• Click on link -> scroll down
  

Explanation

I have done some changes in the code like

• removed ``` and added <code> inside <pre>
• Define language class in <code> and <pre> to specify the language of the code
• replaced some < with < and > with > because it can not be possible to write < or > inside <code> tag due to html rendering: The server was processing the code lines inside the code block which we do not want.

@garg3133 please review this

[garg3133]

Thanks for the PR, @webermayank! I've added it to my todo list and will review it soon.

[garg3133]

Merged, thanks a lot for working on this @webermayank!

The changes will soon be live on https://dev.nightwatchjs.org, please verify over there.

[webermayank]

@garg3133
Yes it is working perfectly on https://dev.nightwatchjs.org/