[pylint] Pylint 2.10 - fix redundant-u-string-prefix

Pylint 2.10 added new default checks [1]:

redundant-u-string-prefix:
  Emitted when the u prefix is added to a string

[1] https://pylint.pycqa.org/en/latest/whatsnew/2.10.html
[2] pylint-dev/pylint#4102

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

tests/unit/test_utils.py

@@ -114,9 +114,9 @@ def test_match_language(self):
     def test_ecma_unscape(self):
         self.assertEqual(utils.ecma_unescape('text%20with%20space'), 'text with space')
         self.assertEqual(utils.ecma_unescape('text using %xx: %F3'),
-                         u'text using %xx: ó')
+                         'text using %xx: ó')
         self.assertEqual(utils.ecma_unescape('text using %u: %u5409, %u4E16%u754c'),
-                         u'text using %u: 吉, 世界')
+                         'text using %u: 吉, 世界')
 
 
 class TestHTMLTextExtractor(SearxTestCase):