fix: make TimePartitioning repr evaluable

[francois-baptiste]

Fixes #109 🦕

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[francois-baptiste]

@googlebot I signed it!

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[plamut]

The main concern with this change, while nice on its own, is that it can break existing user code as the failed tests show. I'm not sure if evaluability of the representation is really worth it.

@shollyman Your thoughts?

[francois-baptiste]

Thank you for your help @plamut.
I reworked the pull request from scratch. The properties from TimePartitioning object are now converted from the REST API to the python API in the repr method.

[plamut]

This is much better, thanks for the refactoring! Changing only the representation is much less of a concern than changing a method signature.

One of the tests broke, though, and should be fixed, the rest are some very minor comments.
(not sure why the CI status is not reported, though...)

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[tseaver]

@shollyman Any follow up on the open internal questions you raised?

[plamut]

@shollyman Friendly ping. :) Any updates on those internal questions to date?

[cguardia]

Looks ready, but seems like nothing can be done until the internal issue is resolved.

[shollyman]

Documentation for behavior is getting updated. Lack of value will be treated as DAY interval.