eng: fix bug in type generation for nullable/union props BNCH-111776#219

eli-bl merged 6 commits intoprod/2.xbenchling/openapi-python-client:prod/2.xfrom

eli.bishop/BNCH-111776-nullablesbenchling/openapi-python-client:eli.bishop/BNCH-111776-nullablesCopy head branch name to clipboard