Fix flaky vtgate test TestInconsistentStateDetectedBuffering (#13560)

go/vt/vtgate/tabletgateway_flaky_test.go

@@ -313,7 +313,11 @@ func TestInconsistentStateDetectedBuffering(t *testing.T) {
 	case <-queryChan:
 		require.Nil(t, res)
 		require.Error(t, err)
-		require.Equal(t, "target: ks1.-80.primary: inconsistent state detected, primary is serving but initially found no available tablet", err.Error())
+		// depending on whether the health check ticks before or after the buffering code, we might get different errors
+		if !(err.Error() == "target: ks1.-80.primary: inconsistent state detected, primary is serving but initially found no available tablet" ||
+			err.Error() == "target: ks1.-80.primary: no healthy tablet available for 'keyspace:\"ks1\" shard:\"-80\" tablet_type:PRIMARY'") {
+			t.Fatalf("wrong error returned: %v", err)
+		}
 	case <-time.After(15 * time.Second):
 		t.Fatalf("timed out waiting for query to execute")
 	}