Update logic in cloud logging exporter to handle various types in LogRecord.attributes#432

DylanRussell merged 3 commits intoGoogleCloudPlatform:mainGoogleCloudPlatform/opentelemetry-operations-python:mainfrom

DylanRussell:fix_attr_to_labelsDylanRussell/opentelemetry-operations-python:fix_attr_to_labelsCopy head branch name to clipboard