Update src/routes/concepts/control-flow/error-boundary.mdx

Co-authored-by: Sarah <gerrardsarah@gmail.com>

Author: amirhhashemi

src/routes/concepts/control-flow/error-boundary.mdx

@@ -38,4 +38,4 @@ function App() {
 ```
 
 In this example, when the `ErrorProne` component throws an error, the `<ErrorBoundary>` catches it, preventing it from affecting the rest of the application.
-Instead, it displays an error message in place of the `ErrorProne` component.
+Instead, it displays the error message passed to the fallback prop.