exporter: user only counter dump/schema commands for extacting counters

exporter: user only counter dump/schema commands for extacting counters

Fixes: https://tracker.ceph.com/issues/59191
Signed-off-by: Avan Thakkar <athakkar@redhat.com>
Ceph exporter no more required the output of perf dump/schema, as the ``counter dump`` command
returns both labeled and unlabeled perf counters which exporter can fetch and export.
Removed the ``exporter_get_labeled_counters`` confiug option as exporter will now export
all the counters, labeled or unlabeled.
Also the fix includes the support for renaming the metrics name of rgw multi-site and
adding labels to it, similar to what is there in prometheus module.