typo fix (#121)

docs/modules/tutorials/pages/concepts/best_practices.adoc

@@ -242,7 +242,7 @@ As your SimpleApplication-based game grows more advanced, you find yourself putt
 
 [NOTE]
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-A game contains algorithms that do not directly affect spatials (for example, AI pathfinding code that calculates and chooses paths, but does not actually move spatials). You do not need to put such non-spatial code in controls, you can run thse things in a new thread. Only the tranformation code that actually modifies the spatial must be called from a control, or must be enqueue()ed.
+A game contains algorithms that do not directly affect spatials (for example, AI pathfinding code that calculates and chooses paths, but does not actually move spatials). You do not need to put such non-spatial code in controls, you can run these things in a new thread. Only the tranformation code that actually modifies the spatial must be called from a control, or must be enqueue()ed.
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