bpo-28395: Remove unnecessary semicolons in tests (GH-26868)

(cherry picked from commit 5a3108044d2e5b694da2d1f4176c9bbaef15c142)

Co-authored-by: Dong-hee Na <donghee.na@python.org>
diff --git a/Lib/test/test_csv.py b/Lib/test/test_csv.py
index a1e050a..225f5c7 100644
--- a/Lib/test/test_csv.py
+++ b/Lib/test/test_csv.py
@@ -157,7 +157,7 @@ def test_write_arg_valid(self):
         self._write_error_test(OSError, BadIterable())
         class BadList:
             def __len__(self):
-                return 10;
+                return 10
             def __getitem__(self, i):
                 if i > 2:
                     raise OSError