Attempted doc warning fix

Author: marcharper

docs/tutorials/contributing/strategy/writing_test_for_the_new_strategy.rst

@@ -23,10 +23,11 @@ how a strategy plays.
 * `first_play_test(action, seed=None)` tests the strategy's first action, taking
 an optional random seed in case the strategy is stochastic. If so, please
 include cases where both outcomes are observed, e.g.::
-
+```
     def test_strategy(self):
         self.first_play_test(C, seed=11)
         self.first_play_test(D, seed=23)
+```
 
 * `second_play_test(rCC, rCD, rDC, rDD, seed=None)` tests the strategies actions
 in the four possible second rounds of play, depending on the move the the