refactor: Add facade around AnalyzerMessage

[slarse]

This is a follow-up on #162, and depends on it. Don't review this until #162 i smerged, I will fix the commit history.

This PR extracts the previously internal SoraldAbstractProcessor.Bug class into a separate sorald.sonar.RuleViolation class, which is just a thin facade around org.java.sonar.AnalyzerMessage. Depending on how we proceed with #156, we may not have access to the actual AnalyzerMessage (but some higher-level abstraction instead), and so this PR is a precaution.

Since the facade was essentially already there in form of the Bug class, this change was very little effort, and also coincidentally cleans up some of the code base. With this change, the only sonar internals we touch in sorald are the check classes, but it doesn't seem reasonable at the moment to put adapters around them. I think we'll leave them be.

[codecov]

Codecov Report

Merging #163 into master will decrease coverage by 0.07%.
The diff coverage is 100.00%.

@@             Coverage Diff              @@
##             master     #163      +/-   ##
============================================
- Coverage     83.44%   83.36%   -0.08%     
- Complexity      354      355       +1     
============================================
  Files            37       38       +1     
  Lines          1558     1551       -7     
  Branches        214      212       -2     
============================================
- Hits           1300     1293       -7     
  Misses          158      158              
  Partials        100      100              

Impacted Files	Coverage Δ	Complexity Δ
src/main/java/sorald/miner/MineSonarWarnings.java	74.01% <100.00%> (+0.41%)	13.00 <0.00> (ø)
...java/sorald/processor/SoraldAbstractProcessor.java	85.48% <100.00%> (-2.98%)	23.00 <0.00> (-2.00)
src/main/java/sorald/sonar/RuleVerifier.java	90.00% <100.00%> (+2.50%)	4.00 <1.00> (ø)
src/main/java/sorald/sonar/RuleViolation.java	100.00% <100.00%> (ø)	3.00 <3.00> (?)

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[slarse]

@fermadeiral Ready for review! Code coverage drop is due to removal of code.

[fermadeiral]

@slarse, thank you for this refactoring.

I noticed you have added documentation in the source code since previous PRs. That is great!

[slarse]

@fermadeiral Glad you like it! I tend to add documentation to most of my code. I enjoy being tidy :)

Sometimes I add too much documentation as I like writing, so you may want to be on the lookout for overly verbose docs where something less verbose would do just fine.