Description of problem: https://access.qa.redhat.com/documentation/en-us/red_hat_ceph_storage/3/html-single/administration_guide/#sizing-considerations-for-bluestore-management includes details about bluestore_cache_size, which users are not required to tune, with the introduction of osd_memory_target. Remove old references and add the procedure to override bluestore block db size and bluestore block wal size using ceph-ansible, based on the guidelines already included in the documentation.
Here is an example of the syntax to use in 'group_vars/all.yml' to override the values for db size and wal size ceph_conf_overrides: osd: bluestore block db size: 14336000000 bluestore block wal size: 2048000000