spelling correction in custom-controls.md (#383)

Author: vigneshsekar314

docs/getting-started/custom-controls.md

@@ -37,7 +37,7 @@ ft.app(main)
 ```
 <img src="/img/docs/custom-controls/styled-controls.png" className="screenshot-20" />
 
-See example of using styled controls in [Calculator App tutotial](/docs/tutorials/python-calculator#styled-controls).
+See example of using styled controls in [Calculator App tutorial](/docs/tutorials/python-calculator#styled-controls).
 
 ### Handling events