ISSUE-6492: [pulsar-bookkeeper] Failed to open rocksdb

[sijie]

Original Issue: apache#6492

---

We got this exception in our production logs:

ERROR org.apache.bookkeeper.statelib.impl.kv.RocksdbKVStore - Failed to open rocksdb at dir /pulsar/data/bookkeeper/ranges/ranges/000000000000000002/000000000000000001/000000000000000000

This incident was associated with an occurrence of this issue: apache#6054
but we haven't been able to track down a distinct cause yet. The error above is the only error that we couldn't pin to some other possible cause, such as a network issue or broker restart, so we're not sure if it's related.