veyron/services/mgmt/node/impl: Reduce test flakiness under -race.
veyron/services/mgmt/node/impl: Reduce test flakiness under -race.

With -race, some operations take more than 1 second, so remove this
timeout from the test.

Change-Id: Ia22d7ff8e08a030ea473a7e3b9d23033c5329cf0

vanadium/go.ref,vanadium/go.ref,vanadium/go.ref,vanadium/go.ref,vanadium/go.ref,vanadium/go.ref