Add comment warning about enabling PulsarMetadataBookieDriver

- upgrade compatibility tests didn't pass with this setting, so more testing is needed

Author: lhotari

charts/pulsar/values.yaml

@@ -912,6 +912,7 @@ pulsar_metadata:
     ## This is a global setting that applies to all BookKeeper components.
     ## When set to true, BookKeeper components will use the PIP-45 metadata driver (PulsarMetadataBookieDriver).
     ## When set to false, BookKeeper components will use BookKeeper's default ZooKeeper connection implementation.
+    ## Warning: Do not enable this feature unless you are aware of the risks and have tested it in non-production environments.
     usePulsarMetadataBookieDriver: false
 
     ## The session timeout for the metadata store in milliseconds. This setting is mapped to `zkTimeout` in `bookkeeper.conf`.