update backup.yaml to fix wkld clusters CI

closes check minio_backup_cert value for wkld-cronjob-testing (#4117)

explanation in sylva-projects/sylva-core#4117 (comment 3692591748)

here in this MR, deploying all the backup units in wkld clusters

raised separate MRs:

• enabling minio-operator in wkld clusters: add minio-operator for wkld cluster (!8924) · Merge requests · Sylva-projects / sylva-core · GitLab
• move the healthcheck from the Kustomization to the HelmRelease for minio-backup - !495 (merged)

changed the endpoint for backup to use minio.minio-backup.svc.cluster.local : !494 (comment 3723491400)

this also needs to be backported in sylva 1.7 and sylva 1.6 so made the changes in 1.7 and 1.6