[logging] End each log line with a newline in TCP
[logging] End each log line with a newline in TCP

This is to match the json_lines codec in logstash to separate out logs
from each other.

Closes: #5524

aptos-labs/aptos-core,libra/libra,aptos-labs/aptos-core,libra/libra,aptos-labs/aptos-core,libra/libra,aptos-labs/aptos-core,aptos-labs/aptos-core,libra/libra,aptos-labs/aptos-core,aptos-labs/aptos-core,libra/libra