fix(rpc): Use populated state in more RPC snapshot tests

[teor2345]

Motivation

We're getting lower test coverage in some of our snapshot tests, because they accidentally use a mock state. We get more coverage by actually calling the state.

Solution

• Rename the mock state instances so we don't accidentally use them
• For one test that failed without the mock state, add a snapshot of that failure

Review

This is a test cleanup, it isn't urgent at all.

Reviewer Checklist

• Will the PR name make sense to users?
  • Does it need extra CHANGELOG info? (new features, breaking changes, large changes)
• Are the PR labels correct?
• Does the code do what the ticket and PR says?
  • Does it change concurrent code, unsafe code, or consensus rules?
• How do you know it works? Does it have tests?

[codecov]

Codecov Report

Merging #6700 (38607ce) into main (185d138) will increase coverage by 0.03%.
The diff coverage is 58.62%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6700      +/-   ##
==========================================
+ Coverage   78.01%   78.05%   +0.03%     
==========================================
  Files         310      310              
  Lines       40740    40757      +17     
==========================================
+ Hits        31784    31812      +28     
+ Misses       8956     8945      -11     

[teor2345]

Failed due to #5819

[upbqdn]

The target branch changed when I was finishing the review on GitHub, which was interesting to observe because the code suddenly changed, and I just kept reading. :D