tests: Add test example files for each public dataset

[prassepaul]

Description

added test files for all the datasets

Fixes issue #569

Checklist:

• [x] My code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] I have made corresponding changes to the documentation
• [x] My changes generate no new warnings
• [x] I have added tests that prove my fix is effective or that my feature works
• [x] New and existing unit tests pass locally with my changes
• [x] Any dependent changes have been merged and published in downstream modules
• [x] I have checked my code and corrected any misspellings

[codecov[bot]]

Codecov Report

All modified lines are covered by tests :white_check_mark:

Comparison is base (cc08c9f) 100.00% compared to head (f7eba77) 100.00%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #581 +/- ## ========================================= Coverage 100.00% 100.00% ========================================= Files 52 52 Lines 2283 2283 Branches 568 568 ========================================= Hits 2283 2283 ```

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