GenAI: Use common env var for content recording#2947

lzchen merged 2 commits intoopen-telemetry:mainopen-telemetry/opentelemetry-python-contrib:mainfrom

lmolkova:rename-openai-env-var-to-genailmolkova/opentelemetry-python-contrib:rename-openai-env-var-to-genaiCopy head branch name to clipboard