ComponentTool: update new test snippet

On recent pylint, this is flagged as unnecessary-pass

Also update the link that was pointing to python2 doc

product/ERP5Type/Tool/ComponentTool.py

@@ -233,7 +233,6 @@ class Test(ERP5TypeTestCase):
     This is ran before anything, used to set the environment
     """
     # here, you can create the categories and objects your test will depend on
-    pass
 
   def test_sampleTest(self):
     """
@@ -242,7 +241,7 @@ class Test(ERP5TypeTestCase):
     For the method to be called during the test,
     its name must start with 'test'.
 
-    See https://docs.python.org/2/library/unittest.html for help with available
+    See https://docs.python.org/library/unittest.html for help with available
     assertion methods.
     """
     self.assertEqual(0, 1)