docs: fix indentation of onlinetest

[kenrick95]

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• I'm making a big change or adding functionality so I've already opened an issue proposing the change to other contributors, so I got feedback on the idea before took the time to write precious code
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Description

Fixing this issue where bad indentation makes the website didn't format correctly

[kenrick95]

Hi @soulgalore please excuse me for the ping, would you check this PR to fix the formatting issue on the docs? Thank you