Fix trailing whitespace in test_numeric_tower

Author: priyanshu2282-cyber

Lib/test/test_numeric_tower.py

@@ -226,7 +226,6 @@ def test_complex(self):
                 self.assertRaises(TypeError, op, v, z)
 
 class IndexMutationDuringNumericOpTest(unittest.TestCase):
-    
     def test_index_mutates_lhs_type_during_operation(self):
         import array