Add a warning in the documentation (#72975)
A partner complained in the name of a customer. They have 6k datasources and it took them some time to figure out why they only had 5k coming back.
This commit add a warning for this edge case, content is pretty clear.
(cherry picked from commit 5eef8291e2)
Co-authored-by: Clément Duveau <clement@duveau.eu>