Python: [BREAKING] Main to core (#983)
* removed pydantic from types
* fix assistants client
* Remove Pydantic usage from workflow code.
* updated lock and test fixes
* moved main to core, and setup meta package
* updated versions
* updated lock
* fixed agents dependency
* added retry to merge tests
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Co-authored-by: Evan Mattson <evan.mattson@microsoft.com>