Backport of "rtpjitterbuffer: Use an extended RTP timestamp for the clock-base" into 1.22
requested to merge gstreamer-backport-bot/gstreamer:mr-6536-backport-into-1.22-rtp-ext-timestamp-fixups into 1.22
Backport of !6536 (merged) "rtpjitterbuffer: Use an extended RTP timestamp for the clock-base".
Commits: