docs: Generate sample for List RPCs

[amanda-tarafa]

Note that for list like operations (e.g. search_folders in resourcemanager v3) we also generate the sample stub, we just don't know (yet) which fields to initialize.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.01%. Comparing base (baf4159) to head (da8c37b).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4641      +/-   ##
==========================================
+ Coverage   95.00%   95.01%   +0.01%     
==========================================
  Files         196      196              
  Lines        7525     7525              
==========================================
+ Hits         7149     7150       +1     
+ Misses        376      375       -1     

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[amanda-tarafa]

This is now ready for review.