[branch-4.16] fix: reference counting (retain/release) in PerChannelBookieClient

[zhiheng123]

This addresses the remaining gaps of #4289 in handling ByteBuf retain/release. This PR will also address the concern about NioBuffer lifecycle brought up in the review of the original PR review: #791 (comment) .

This PR fixes several problems:

• ByteString buffer lifecycle in client, follows ByteBufList lifecycle
• ByteBufList lifecycle, moved to write promise
• Calling of write promises in AuthHandler which buffers messages while authentication is in progress. It was ignoring the promises.

• add 2 callback parameters to writeAndFlush: cleanupActionFailedBeforeWrite and cleanupActionAfterWrite
  • use these callback actions for proper cleanup
• extract a utility class ByteStringUtil for wrapping ByteBufList or ByteBuf as concatenated zero copy ByteString
• properly handle releasing of ByteBufList in the write promise
• properly handle calling promises that are buffered while authentication is in progress

Descriptions of the changes in this PR:

Fix #xyz

Main Issue: #xyz

BP: #xyz

Motivation

(Explain: why you're making that change, what is the problem you're trying to solve)

Changes

(Describe: what changes you have made)

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[hezhangjian]

@lhotari PTAL

[hezhangjian]

Error: Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.12.1:compile (default-compile) on project bookkeeper-server: Compilation failure: Compilation failure:
Error: /home/runner/work/bookkeeper/bookkeeper/bookkeeper-server/src/main/java/org/apache/bookkeeper/proto/PerChannelBookieClient.java:[1002,29] cannot find symbol
Error: symbol: class BatchedReadEntryCallback
Error: location: class org.apache.bookkeeper.proto.PerChannelBookieClient
Error: /home/runner/work/bookkeeper/bookkeeper/bookkeeper-server/src/main/java/org/apache/bookkeeper/proto/PerChannelBookieClient.java:[1019,44] cannot find symbol
Error: symbol: class BatchedReadEntryCallback
Error: location: class org.apache.bookkeeper.proto.PerChannelBookieClient
Error: -> [Help 1]