upgpkg: 6.7.1-1

This bumps Streamlink the latest version and adds the missing python-exceptiongroup runtime dependency.

Yesterday there was an issue with python-pytest where 8.x was still not packaged due to a packaging bug and missing compatibility version of python-pytest-asyncio, but this has been resolved now and pytest has been bumped to the latest version, so streamlink==6.7.1 will now build without any issues:
python-pytest#1 (closed)