Don't call set attribute twice for the same key and make start attributes unsettable#150

lmolkova wants to merge 4 commits into

open-telemetry:mainopen-telemetry/opentelemetry-python-genai:mainfrom

lmolkova:dont-duplicate-attributeslmolkova/opentelemetry-python-genai:dont-duplicate-attributesCopy head branch name to clipboard