minor #11512 Correct method name in example (rgagnon24)

This PR was submitted for the 4.2 branch but it was merged into the 3.4 branch instead (closes #11512).

Discussion
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Correct method name in example

The "new in 1.26" example references a method in the initial example that was named "formatPrice" yet the documentation referred to it as "priceFilter".

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Commits
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e41f32f Correct method name in example

Author: javiereguiluz

templating/twig_extension.rst

@@ -34,11 +34,11 @@ Create a class that extends ``AbstractExtension`` and fill in the logic::
         public function getFilters()
         {
             return [
-                new TwigFilter('price', [$this, 'formatPrice']),
+                new TwigFilter('price', [$this, 'priceFilter']),
             ];
         }
 
-        public function formatPrice($number, $decimals = 0, $decPoint = '.', $thousandsSep = ',')
+        public function priceFilter($number, $decimals = 0, $decPoint = '.', $thousandsSep = ',')
         {
             $price = number_format($number, $decimals, $decPoint, $thousandsSep);
             $price = '$'.$price;