Moved test classes to test sources

[remcowesterhoud]

Description

Somehow these tests ended up in the source files, instead of the test source files. Presumably due to the module split. This moves them back where they belong.

Also modified the junit dependency scope to test. Now that these files are moved the junit is no longer used outside of the test scope.

Definition of Done

Not all items need to be done depending on the issue and the pull request.

Code changes:

• The changes are backwards compatibility with previous versions
• If it fixes a bug then PRs are created to backport the fix

Testing:

• There are unit/integration tests that verify all acceptance criterias of the issue
• New tests are written to ensure backwards compatibility with further versions
• The behavior is tested manually

Documentation:

• Javadoc has been written
• The documentation is updated

[github-actions]

Unit Test Results

  90 files    90 suites   4m 19s ⏱️
192 tests 192 ✔️ 0 💤 0 ❌
576 runs  576 ✔️ 0 💤 0 ❌

Results for commit 431cbcf.

♻️ This comment has been updated with latest results.

[saig0]

LGTM 👍