Pass list of params to pytest.main() in docs

doc/en/usage.rst

@@ -318,7 +318,7 @@ You can specify additional plugins to ``pytest.main``::
         def pytest_sessionfinish(self):
             print("*** test run reporting finishing")
 
-    pytest.main("-qq", plugins=[MyPlugin()])
+    pytest.main(["-qq"], plugins=[MyPlugin()])
 
 Running it will show that ``MyPlugin`` was added and its
 hook was invoked::
@@ -326,7 +326,5 @@ hook was invoked::
     $ python myinvoke.py
     *** test run reporting finishing
     
-    ======= pytest-warning summary ========
-    WC1 None passing a string to pytest.main() is deprecated, pass a list of arguments instead.
 
 .. include:: links.inc