fix assertions on byzantine test (#5171)

consensus/byzantine_test.go

@@ -167,13 +167,14 @@ func TestByzantinePrevoteEquivocation(t *testing.T) {
 		msg := <-blocksSubs[j].Out()
 		block := msg.Data().(types.EventDataNewBlock).Block
 		// assert that we have evidence
-		require.True(t, len(block.Evidence.Evidence) == 1)
-		// and that the evidence is of type DuplicateVoteEvidence
-		ev, ok := block.Evidence.Evidence[0].(*types.DuplicateVoteEvidence)
-		assert.True(t, ok)
-		// and that the address matches to that of the byzantine node
-		pubkey, _ := bcs.privValidator.GetPubKey()
-		assert.Equal(t, []byte(pubkey.Address()), ev.Address())
+		if assert.True(t, len(block.Evidence.Evidence) == 1) {
+			// and that the evidence is of type DuplicateVoteEvidence
+			ev, ok := block.Evidence.Evidence[0].(*types.DuplicateVoteEvidence)
+			assert.True(t, ok)
+			// and that the address matches to that of the byzantine node
+			pubkey, _ := bcs.privValidator.GetPubKey()
+			assert.Equal(t, []byte(pubkey.Address()), ev.Address())
+		}
 	}, css)
 }