fix(i): Sort out invalid testing framework node indexing

[shahzadlone]

Relevant issue(s)

Resolves #3065

Description

The main bug was only visible on sourcehub acp using http, due to the identity being copied with the audience value of another node's host failing authentication (the bearer tokens should be unique using correct node's audience). The biggest issue was the way we use getNodes and getNodeCollections. I would be in favor of completely removing them as they are more troublesome than the utility they provide.

• First commit documents the bug
• Some utility functions were overwriting and producing the wrong node index
• Forbidden bug happening on sourcehub<>http test run: https://github.com/sourcenetwork/defradb/actions/runs/10930293192/job/30342883535?pr=2907

Future:

• Resolve import/export documentation and implementation if different (Backup import and export for all nodes or just first #3067)
• Should likely clean this test utils up and make helper methods to avoid code duplication (Clean up test utils, make helpers to avoid code duplication and remove confusing util functions #3069)
• Likely should remove all usages of getNodeCollections (Clean up test utils, make helpers to avoid code duplication and remove confusing util functions #3069)
• Likely should remove all usages of getNodes (Clean up test utils, make helpers to avoid code duplication and remove confusing util functions #3069)

How has this been tested?

• Very painfully haha, had to install Linux bare-metal to investigate the first bug (sourcehub doesn't build on wsl for me) that was only occurring on sourcehub acp using http, due to the identity being copied with the audience value of another node the way we use getNodes and getNodeCollections

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 79.36%. Comparing base (79eb12c) to head (6b9be21).
Report is 1 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #3068      +/-   ##
===========================================
+ Coverage    79.35%   79.36%   +0.01%     
===========================================
  Files          345      345              
  Lines        26557    26557              
===========================================
+ Hits         21074    21076       +2     
+ Misses        3956     3955       -1     
+ Partials      1527     1526       -1     

Flag	Coverage Δ
all-tests	79.36% <ø> (+0.01%)	⬆️

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see 6 files with indirect coverage changes

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[nasdf]

LGTM. Thanks for documenting everything so well. I'm also in favor of removing the getNodes utilities.