Fixes cache issue from 703 and 679 (#707)

* Avoid creating cache database when cache_seed is None (which disables cache)

* Add some debugging.

* Removed some debugging.

* Update autogen/oai/client.py

Co-authored-by: Chi Wang <wang.chi@microsoft.com>

* Fixed missing filter function logic from oai/client.py

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Co-authored-by: Chi Wang <wang.chi@microsoft.com>