Add `rc_presence` ratelimiting config to demo/start.sh #4747

Job	Run time
Calculate list of debian distros	8s
Build sdist	0s
Build wheels on ubuntu-22.04 for x86_64	1m 46s
Build .deb packages (debian:sid)	9m 21s
Attach assets to release	0s
	11m 15s

Provide feedback