Fix the bullet points for the timer nodes in The main game scene (#4897)

The text in second line for each of the bullets was not being included in the bullet due to improper spacing.

getting_started/first_2d_game/05.the_main_game_scene.rst

@@ -15,13 +15,13 @@ Now, add the following nodes as children of ``Main``, and name them as shown
 (values are in seconds):
 
 - :ref:`Timer <class_Timer>` (named ``MobTimer``) - to control how often mobs
-   spawn
+  spawn
 - :ref:`Timer <class_Timer>` (named ``ScoreTimer``) - to increment the score
-   every second
+  every second
 - :ref:`Timer <class_Timer>` (named ``StartTimer``) - to give a delay before
-   starting
+  starting
 - :ref:`Position2D <class_Position2D>` (named ``StartPosition``) - to indicate
-   the player's start position
+  the player's start position
 
 Set the ``Wait Time`` property of each of the ``Timer`` nodes as follows: