fix: Support both "data:" and "data: " formats for streaming responses#2584

CaroyalKnight wants to merge 3 commits into

googleapis:maingoogleapis/python-genai:mainfrom

CaroyalKnight:fix/handle-stream-data-colon-variantCaroyalKnight/python-genai:fix/handle-stream-data-colon-variantCopy head branch name to clipboard