apache / bookkeeper / 904

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jenkins

Bookie Client add quarantine ratio when error count exceed threshold

### Motivation
When bookie client read/write data from/to bookie servers, it will check the health of each connected server in sepecific interval. Once the amount of errors reached the threshold, the bookie server will be quarantined for server miniutes (configurated by `bookieQuarantineTimeSeconds`) by the bookie client.

In most circumstance, there are large amount of bookie clients connected to one bookie server, like pulsar broker. Once the bookie server runs in heavy load, most of bookie clients will receive errors and trigger quarantine in the same time, and then quarantine the server for several miniutes. After a few miniutes passed by, the quarantined server will be put back in the same time for most bookie clients, which will lead to periodic oscillation of in/out throughput of the server. It is the obstacle of tunning the throughput of the bookkeeper cluster.

### Changes
I introduce a quarantine probability to determine whether to quarantine the server for the client, avoiding quaraninte the heavy load server in the same time for most of bookie client.

I also expose the quarantine stats to prometheus.

Reviewers: Jia Zhai <zhaijia@apache.org>, Sijie Guo <None>

This closes #2327 from hangc0276/bookieClient_Quarantine_ratio

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