Further fix indentation in 'play an animation' procedure

Author: birtles

Overview.bs

@@ -1172,12 +1172,12 @@ as CSS Animations [[CSS3-ANIMATIONS]].
             before its <a>current finished promise</a>.
         </div>
 
-        So long as the above task is scheduled but has yet to run,
-        <var>animation</var> is described as having a
-        <dfn>pending play task</dfn>.
+    So long as the above task is scheduled but has yet to run,
+    <var>animation</var> is described as having a
+    <dfn>pending play task</dfn>.
 
-        A user agent MAY execute the above task immediately (if it
-        determines <var>animation</var> is immediately <a>ready</a>).
+    A user agent MAY execute the above task immediately (if it
+    determines <var>animation</var> is immediately <a>ready</a>).
 
 1.  Run the procedure to <a>update an animation's finished state</a> for
     <var>animation</var> with the <var>did seek</var> flag set to false, and