BUG(duplication): When "duplicate_log_batch_bytes" is greater than 0 , there is a probability that some data will be lost.

[lengyuexuexuan]

Bug Report

1. What did you do? https://github.com/apache/incubator-pegasus/blob/e42f1a65f0b7352c531e2bc90a9ac434e52ffe98/src/server/pegasus_mutation_duplicator.cpp#L251-L270

• The "muts" contain multiple mutations.
• When the RPC code of the last mutation is "RPC_RRDB_RRDB_DUPLICATE" or "RPC_RRDB_RRDB_BULK_LOAD", will execute "continue", not push duplicate_rpc into "_inflights".
• But the last_decree has updated, the next time the logs are loaded, these mutations will not be read again.

[acelyc111]

@empiredan Please take a look