Fix wspr test.  It was using "fmt.Errorf" instead of "t.Errorf", so we never knew it was failing before.
Fix wspr test.  It was using "fmt.Errorf" instead of "t.Errorf", so we
never knew it was failing before.

Change-Id: I77cb1e51aa5a112887a936bc61431169e78ecb21

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