[#593][part-2] feat(netty): WriteBuffer use ByteBuf

[xumanbu]

What changes were proposed in this pull request?

1. WriteBuffer use ByteBuf instead byte array.

Why are the changes needed?

Fix: #593

Does this PR introduce any user-facing change?

(Please list the user-facing changes introduced by your change, including

1. Change in user-facing APIs.
2. Addition or removal of property keys.)

No.

How was this patch tested?

UT