Add unit-tests for depgraph query

[Helcaraxan]

Pull Request

Checklist

• Changes are lint-free. You can check this by running ./ci/lint.sh or by opening a draft PR
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• All tests pass. You can check this by running ./ci/test.sh or by opening a draft PR to
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• If relevant, tests have been updated or added to ensure your changes will not be reverted or
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Summary

Unit-tests for the graph querying logic! Related to #19. 🥳

Tests

Tests, tests, tests everywhere!