[docs] fix transition direction options (#8133)

Author: geoffrich

site/content/docs/03-template-syntax.md

@@ -1099,7 +1099,7 @@ Transition functions also receive a third argument, `options`, which contains in
 
 Available values in the `options` object are:
 
-* `direction` - one of `in`, `out`, or `bidirectional` depending on the type of transition
+* `direction` - one of `in`, `out`, or `both` depending on the type of transition
 
 ##### Transition events