Remove newlines from raft_consensus.cc state logging
Remove newlines from raft_consensus.cc state logging

Removes an explicit newline from ReplicaState::ToStringUnlocked, which
was causing split log lines in raft_consensus.cc.

Before:

    I0930 15:01:06.197114 292159488 raft_consensus.cc:505] T 00000000000000000000000000000000 P a65e9f463a254ae1a7e34a1a8e4cc7cc [term 0 FOLLOWER]: Becoming Follower/Learner. State: Replica: a65e9f463a254ae1a7e34a1a8e4cc7cc, State: 1, Role: FOLLOWER
    Watermarks: {Received: term: 0 index: 0 Committed: term: 0 index: 0}

After:

    I0930 14:51:09.334908 360529920 raft_consensus.cc:505] T 00000000000000000000000000000000 P d2878bd460384b8ab58dd3aaf2c8f52d [term 0 FOLLOWER]: Becoming Follower/Learner. State: Replica: d2878bd460384b8ab58dd3aaf2c8f52d, State: 1, Role: FOLLOWER, Watermarks: {Received: term: 0 index: 0, Committed: term: 0 index: 0}

Change-Id: If1f3db96ece79e81b42bce4db51d37f14df14f50
Reviewed-on: http://gerrit.cloudera.org:8080/4580
Tested-by: Kudu Jenkins
Reviewed-by: David Ribeiro Alves <78b9f953b197533e9b51c860b080869056433b48@apache.org>

andrwng/kudu,EvilMcJerkface/kudu,helifu/kudu,EvilMcJerkface/kudu,andrwng/kudu,InspurUSA/kudu,InspurUSA/kudu,InspurUSA/kudu,InspurUSA/kudu,InspurUSA/kudu,andrwng/kudu,cloudera/kudu,EvilMcJerkface/kudu,cloudera/kudu,cloudera/kudu,helifu/kudu,InspurUSA/kudu,helifu/kudu,EvilMcJerkface/kudu,cloudera/kudu,cloudera/kudu,helifu/kudu,andrwng/kudu,EvilMcJerkface/kudu,helifu/kudu,andrwng/kudu,cloudera/kudu,helifu/kudu,helifu/kudu,EvilMcJerkface/kudu,EvilMcJerkface/kudu,cloudera/kudu,InspurUSA/kudu,helifu/kudu,EvilMcJerkface/kudu,cloudera/kudu,helifu/kudu,andrwng/kudu,andrwng/kudu,andrwng/kudu,EvilMcJerkface/kudu,andrwng/kudu,cloudera/kudu,InspurUSA/kudu,InspurUSA/kudu