Add example code for the empty string comparison on the docs

[donRehan]

I am a beginner and spent some time playing with quick-lint so I can understand it and contribute to it. One of the main issues to me was that the code to write empty string comparison was not clear and only recently I was able to do it.

Hence is why I wanted to ask if that's something you are interested in to have on the docs website an example code to showcase how we would write the code to detect the empty string comparison . If that's fine by you I will open a pull request and add that to the documentation.
Thank you in advance.

[donRehan]

@strager

I am talking about this part in the https://quick-lint-js.com/contribute/create-diagnostic/

Detecting when to report the diagnostic is up to you. But once you have the information you need, reporting a diagnostics is easy:

I would go ahead and add a sample that does that explaining what it does to make it helpful for others who are also beginners and want to understand how things work.

Please let me know within this week if you are fine with this or not. Thank you in advance.