polar-doc: question about avail-parallel-replay.md

[ForestLH]

Describe the problem

Hi everyone!
我才接触PolarDB，我想请教一个小问题，这里的$Block_{0,2} = Block_{2,0}$是对的吗，这两个不是一个Block0呀，一个是Block2呀

https://github.com/ApsaraDB/PolarDB-for-PostgreSQL/blob/bbc102d852c4aa202bd08fc8127ebb2d33cc0be4/polar-doc/docs/zh/features/v11/availability/avail-parallel-replay.md?plain=1#L52C60-L52C87

谢谢

[polardb-bot]

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