Rework of UnitsNetJsonConverter

[dschuermans]

Fixes #732.

Reworked UnitsNetJsonConverter according to #732.
Also split up serialization and deserialization tests into seperate files for better readability and extracted test objects into their own classes. Consider this an overall clean-up of the test project

[codecov-io]

Codecov Report

Merging #746 into master will increase coverage by 0.96%.
The diff coverage is 97.75%.

@@            Coverage Diff             @@
##           master     #746      +/-   ##
==========================================
+ Coverage   61.92%   62.89%   +0.96%     
==========================================
  Files         171      273     +102     
  Lines       38457    39630    +1173     
==========================================
+ Hits        23814    24924    +1110     
- Misses      14643    14706      +63

Impacted Files	Coverage Δ
...Net.Serialization.JsonNet/UnitsNetJsonConverter.cs	42.96% <ø> (-43.07%)	⬇️
...Serialization.JsonNet/Internal/ReflectionHelper.cs	44.44% <ø> (-8.89%)	⬇️
...Serialization.JsonNet/UnitsNetBaseJsonConverter.cs	100% <100%> (ø)
...lization.JsonNet/UnitsNetIQuantityJsonConverter.cs	100% <100%> (ø)
...zation.JsonNet/UnitsNetIComparableJsonConverter.cs	90% <90%> (ø)
UnitsNet/GeneratedCode/UnitConverter.g.cs	100% <0%> (ø)	⬆️
...ns/GeneratedCode/NumberToLuminosityExtensions.g.cs	100% <0%> (ø)
...nsions/GeneratedCode/NumberToEnergyExtensions.g.cs	100% <0%> (ø)
... and 101 more

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[dschuermans]

@angularsen If you want better code coverage, I could always update the unit tests to also test the actual converters.
The current tests are actually integration tests if you look at it 😮

[dschuermans]

Okay, i'm adding tests for the converters themselves at the moment 😄

[dschuermans]

Okay, i'm done now 👍

[angularsen]

Perfect, I'll try to take a look later today.

[angularsen]

Haha, that is fine by me 😆 In my experience, it is extremely rare that such constants in test code change. When they do, either it is a matter of simple search/replace or there is a bigger conceptual change that requires rewriting the tests anyway. Time spent reading code vs writing code is probably some tens of times more, so I always favor readability.

[angularsen]

Great job, thanks!

[angularsen]

Release UnitsNet/4.45.0 · angularsen/UnitsNet