Fix unit test

Author: tammy-baylis-swi

instrumentation/opentelemetry-instrumentation-psycopg2/tests/test_psycopg2_integration.py

@@ -208,6 +208,7 @@ def test_instrument_connection_with_instrument(self):
         self.assertEqual(len(spans_list), 0)
 
         Psycopg2Instrumentor().instrument()
+        cnx = psycopg2.connect(database="test")
         cnx = Psycopg2Instrumentor().instrument_connection(cnx)
         cursor = cnx.cursor()
         cursor.execute(query)