fix: use correct function name (#8171)

Author: FelixTraxler

src/content/reference/react/addTransitionType.md

@@ -39,7 +39,7 @@ startTransition(() => {
 
 #### Returns {/*returns*/}
 
-`startTransition` does not return anything.
+`addTransitionType` does not return anything.
 
 #### Caveats {/*caveats*/}