Fix typo in test's docstring (GH-17856) (GH-17923)

* Fix typo in test's docstring. contination -> continuation.
(cherry picked from commit 2f65aa4)

Co-authored-by: Daniel Hahler <git@thequod.de>

Co-authored-by: Daniel Hahler <github@thequod.de>

Author: 2 people

Lib/test/test_eof.py

@@ -27,7 +27,7 @@ def test_EOFS(self):
             raise support.TestFailed
 
     def test_line_continuation_EOF(self):
-        """A contination at the end of input must be an error; bpo2180."""
+        """A continuation at the end of input must be an error; bpo2180."""
         expect = 'unexpected EOF while parsing (<string>, line 1)'
         with self.assertRaises(SyntaxError) as excinfo:
             exec('x = 5\\')