test: raise library test coverage

[bconn98]

Fixes #352 + Adds a ton of tests

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 66.66667% with 1 lines in your changes are missing coverage. Please review.

Project coverage is 84.61%. Comparing base (c981ca4) to head (4a56b4e).

Files	Patch %	Lines
src/encode/json.rs	50.00%	1 Missing ⚠️

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Additional details and impacted files

@@             Coverage Diff             @@
##             main     #349       +/-   ##
===========================================
+ Coverage   63.01%   84.61%   +21.59%     
===========================================
  Files          24       24               
  Lines        1560     1566        +6     
===========================================
+ Hits          983     1325      +342     
+ Misses        577      241      -336     

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[bconn98]

Ready for review

[estk]

why rm?

[estk]

so, i just pulled the thread and although gzip is no-longer part of the default features, I still think a warning regarding the use of gzip is important to be featured in the readme... perhaps not as prominently. Also, this change should be pulled out into a separate PR.

[estk]

I think we should break this up into a few separate PR's, there are too many disparate changes here to review it without sitting down for at least a few hours... which is difficult to find these days.

Can you please open separate PR's with cohesive motif's? Some possible MR's

• Config tests
• Encoder tests
• Filter tests
• Integration tests
• Appender tests
• Compound appender tests

In each PR please:

1. Call out any changes to code outside of mod test & why its needed
2. for each test, if it is not obvious why it needs to exists, please add a brief description

[bconn98]

Broke into the following PRs:

• compound appenders
• config
• filter
• integration
• encode
• appender
• readme