Set `gen_ai.operation.name` correctly in `openai-agents`

[alexander-alderman-webb]

openai-agents can also call the responses API, for example:

sentry-python/sentry_sdk/integrations/openai_agents/spans/ai_client.py

Line 37 in 53188b3

span.set_data(SPANDATA.GEN_AI_OPERATION_NAME, "chat")

[linear-code]

PY-2497