How to upgrade from RHCS 4.2z4 to 5.0z4 provided 5.1 is already GA'd

Issue

• RGW MultiSite is not available with RHCS 5.1.
• Any MultiSite customer who wants to upgrade from 4.2z4 to 5.0z4, they have to update few packages like ceph-ansible, cephadm, cephadm-ansible.
• Since RHCS 5.1 is already GA'd, updating those packages will pull the latest versions. However we need to manually downgrade the version needed for 5.0z4.
• Similarly, for 5.0z4 fresh install, make sure to install a compatible version of cephadm-ansible and cephadm package. This is needed because in RHCS 5.1, cephadm bootstrap command has to run with ''--yes-i-know" flag.
• This article will document a few steps to be remembered while following the Installation Guide in order to upgrade to RHCS 5.0z4 so that customer doesn't need to worry about extra flags.