test(pubsub): add resume publish with ordering key sample

[suzmue]

This is a very simple example for how to resume_publish with an ordering key. A more complex example may provide better guidance for how to recover from this use case, but this is about the depth the other samples go into for other languages.

I am working on writing a more interesting example, but I think it would benefit in review to have the simple example to compare to so we can see if that is an actual improvement in clarity or not and this example provides some benefit over it not existing at all.

Fixes #5034

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.87%. Comparing base (da91d77) to head (f0d61e4).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #5035   +/-   ##
=======================================
  Coverage   91.87%   91.87%           
=======================================
  Files         230      230           
  Lines        8797     8797           
=======================================
  Hits         8082     8082           
  Misses        715      715           

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[dbolduc]

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