test: Refactor tests using large single-line JSON strings

[chynesNR]

This ended up being more tedious than expected. Using raw string literals makes the code much more readable, but the tests are expecting an exact match, and I couldn't just strip the whitespace because some values contain spaces. For that I added an "unformatting" helper function.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 80.60%. Comparing base (d51a54c) to head (c705409).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2559      +/-   ##
==========================================
- Coverage   80.61%   80.60%   -0.01%     
==========================================
  Files         459      459              
  Lines       28927    28927              
  Branches     3177     3177              
==========================================
- Hits        23319    23317       -2     
- Misses       4819     4821       +2     
  Partials      789      789              

Flag	Coverage Δ
Agent	81.50% <ø> (-0.01%)	⬇️
Profiler	72.59% <ø> (ø)

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see 2 files with indirect coverage changes

[tippmar-nr]

Nice. Should really help readability.