test: Retry all RPC commands to fix MacOS CI jobs

[ximinez]

High Level Overview of Change

Retry all failed RPC connections / commands in unit tests.

Context of Change

Follow up to #5120 (23991c9), which added a retry for submit commands. It improved MacOS test reliability, but other tests are failing now.

Type of Change

• [X] Bug fix (non-breaking change which fixes an issue)
• [X] Tests (you added tests for code that already exists, or your new feature included in this PR)

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.

Project coverage is 78.0%. Comparing base (ed4870c) to head (a63f0c5). Report is 2 commits behind head on develop.

Files with missing lines	Patch %	Lines
include/xrpl/server/detail/Door.h	0.0%	2 Missing :warning:

Additional details and impacted files

@@            Coverage Diff            @@
##           develop   #5171     +/-   ##
=========================================
- Coverage     78.0%   78.0%   -0.0%     
=========================================
  Files          789     789             
  Lines        67007   67008      +1     
  Branches      8110    8109      -1     
=========================================
  Hits         52274   52274             
- Misses       14733   14734      +1     

Files with missing lines	Coverage Δ
include/xrpl/server/detail/Door.h	79.3% <0.0%> (ø)

... and 5 files with indirect coverage changes

[ximinez]

@thejohnfreeman @vlntb I want to bring your attention to draft PR #5180. It builds on top of this PR, but adds three commits:

1. The MacOS CI jobs have 4 configurations: The combinations of release vs debug, and unity vs non-unity.
2. The Env tests cycle through a range of ports so that if the OS is slow to close a port when one test ends, the next test doesn't immediately try to open it. A general retry operation is added so that lower-level network issues can also be retried, not just failed RPC commands.
3. The MacOS CI jobs use parallel runners! (It only uses half the available CPU threads, because using all was still not reliable, but it's better than nothing!)

I would like to roll those changes into this PR so we can get the MacOS jobs fixed all in one shot. Do you think that's a good idea, or should that be a separate PR to be merged separately sometime after this one?

[thejohnfreeman]

I don't see any approvals in here yet, so I say roll them into this PR.

[ximinez]

Closed in favor of #5196