impl(pubsub): add options for lease RPCs

[dbolduc]

Part of the work for #4471

Introduce retry options for lease operations that can withstand an hourly connection reset.

Note that the options are not in use yet. The next PR will hook them up to the client.

[dbolduc]

Note to the reviewer:

TIL: #[track_caller] which will display the caller's line number on failed asserts in this function. It does not display the line number that fails in this file, which is why I went for very descriptive error messages.

This is factored out because I will reuse it from leaser.rs in my next PR.

cc: @PhongChuong because you might get a kick out of this.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.02%. Comparing base (609a638) to head (a494438).
⚠️ Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4573      +/-   ##
==========================================
+ Coverage   95.00%   95.02%   +0.02%     
==========================================
  Files         195      195              
  Lines        7449     7459      +10     
==========================================
+ Hits         7077     7088      +11     
+ Misses        372      371       -1     

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