docs: add example of Modify (redefine) response only to particular endpoint

[pavelsr]

Summary

First off all, Sean @WSH032, thanks for this library

I added one more example to Advanced usage

My example can be useful for API A/B testing or hiding particular methods of upstream

Close: #36

Checklist

• I've read CONTRIBUTING.md.
• I understand that this PR may be closed in case there was no previous discussion. (This doesn't apply to typos!)
• I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
• I've updated the documentation accordingly.

[WSH032]

Hi @pavelsr ! Well done! 🎉 Every pull request targeting the documentation is appreciated! Thank you for your contribution!

I have left some reviews, could you take a look at them?

The CI pipeline encountered some errors, but don't worry, I'll fix it.

[WSH032]

The CI pipeline encountered some issues from the upstream (codecov/feedback#358).

#28 Upgrading to codecov-action v4 might resolve this issue. I'll test it out and see if the upgrade works.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.97%. Comparing base (558a86b) to head (89682c5).
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #37      +/-   ##
==========================================
+ Coverage   96.96%   96.97%   +0.01%     
==========================================
  Files           9        9              
  Lines         461      463       +2     
  Branches       44       35       -9     
==========================================
+ Hits          447      449       +2     
  Misses          9        9              
  Partials        5        5              

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[WSH032]

ping @pavelsr, do you still want to push this PR? I will modify and merge it today, let me know if you have any comments.

[WSH032]

I have already made the changes. If you have no other comments, I will merge this PR in a few hours.