Update test_sfg.py

test/test_sfg.py

@@ -1424,7 +1424,7 @@ class TestSFGErrors:
         out1 = Output(adaptor.output(0))
         signal = Signal(adaptor.output(1))
         with pytest.raises(
-            ValueError, match="At least one output operation is not connected!, Tips: Check for output ports that are connected to the  same signal"
+            ValueError, match="At least one output operation is not connected!, Tips: Check for output ports that are connected to the same signal"
         ):
             SFG([in1, in2], [out1], output_signals=[signal, signal])