This PR changes the handling of bucket deletes for site
replicated setups to hold on to deleted bucket state until
it syncs to all the clusters participating in site replication.
The current code considers a pool with all root disks to be as part
of a testing environment even if there are other pools with mounted
disks. This will result to illegitimate writing in root disks.
Fix this by simplifing the logic: require MINIO_CI_CD in order to skip
root disk check.
