Add tests to checkstyle

[tadgh]

• Add tests to checkstyle
• Suppress various hamcrest complaints until we fix them
• Name suppression modules:
  • HapiErrorCodeUniqueness
  • NoPrintln
• Work on suppressions:
  • unsuppress tests
  • suppress hapi error checker in test files
  • suppress hamcrest complaints in MDM
• You can now suppress checkstyle warnings on classes/methods by annotating with the ID of the check.

  @SuppressWarnings("checkstyle:NoPrintln")

[github-actions[bot]]

Formatting check succeeded!

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 83.46%. Comparing base (497b9f2) to head (c0626bb). Report is 95 commits behind head on master.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #6006 +/- ## ============================================ + Coverage 83.39% 83.46% +0.06% - Complexity 26927 27237 +310 ============================================ Files 1681 1697 +16 Lines 103965 105320 +1355 Branches 13189 13311 +122 ============================================ + Hits 86702 87902 +1200 - Misses 11613 11718 +105 - Partials 5650 5700 +50 ```

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