* add back streaming for base o3 (#8361)
* test(base_llm_unit_tests.py): add base test for o-series models - ensure streaming always works
* fix(base_llm_unit_tests.py): fix test for o series models
* refactor: move test
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Co-authored-by: Matteo Boschini <12133566+mbosc@users.noreply.github.com>