Remove unnecessary tests

What does this MR do and why?

Currently, these tests aggregates little value because:

• As far as I understand, these tests are validating that the JSON scheme library is working as expected, I think we should trust it works;
• These tests are getting more and more complex, by trying to add more examples of invalid jsons (example of conversation around that: !92690 (comment 1046808685));

More information in: #369417 (closed)

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