Fix flakiness in MultiThreadedRpcTest.TestBlowOutServiceQueue
Fix flakiness in MultiThreadedRpcTest.TestBlowOutServiceQueue

Commit eded05723e changed the error message returned by Socket::Recv
when EOF is received from the remote. The corresponding string used for
matching in TestBlowOutServiceQueue was not updated, so in rare
circumstances the test would fail because it saw an unexpected error
message.

Change-Id: I952f4a01ecf73de5c92c6b0820b9176dde0a5a8f
Reviewed-on: http://gerrit.cloudera.org:8080/11705
Tested-by: Kudu Jenkins
Reviewed-by: Adar Dembo <866ca730bfc7f544e3ebce604ceeba4879f23df0@cloudera.com>

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