Do not offline the signing node. Right now we only run tag-releases on
Add also a note to our REVIEWING list about these long-lived nodes.
Recent review Id8e5d55e34ec3b3d555b5482e13f99c2561e871e removed
check-requirements job without removing the project from
projects.txt in requirements repo. It caused a voting gate to
fail all the reviews submitted.
Updated REVIEWING.rst to verify this before approving
removal of check-requirements job.