fix: handle empty or incomplete conferencing objects in events#432

AaronDDM merged 2 commits intomainnylas/nylas-python:mainfrom

CUST-4680-v-3-python-sdk-fails-to-handle-events-with-empty-conferencing-objectsnylas/nylas-python:CUST-4680-v-3-python-sdk-fails-to-handle-events-with-empty-conferencing-objectsCopy head branch name to clipboard