Provide a richer set of test cases for the Python API client

[ianhinder]

The current set of tests in test_standard_api.py, and the corresponding data in tests/data, is a bit limited. For example, it would be good to have:

• [ ] Arrays of dimension > 1 (for testing layout issues)
• [ ] Tables with columns of different types
• [ ] Arrays of different types (maybe only int32 and float64?)
• [ ] Parameters of different types
• [ ] Different distributions, as well as different types of their parameters (though maybe we want to restrict to float64 for distribution parameters for simplicity)

[github-actions[bot]]

Heads up @mrow84 @bobturneruk - the "data pipeline api" label was applied to this issue.