bug #153 Skipping null values from rendering (sadikoff)

This PR was squashed before being merged into the main branch.

Discussion
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Skipping null values from rendering

Hi there!

This should fix a weird situation when we are rendering stringified `null` value attribute and stimulus using `null` string as a value instead of just skipping it.

Commits
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20bc66d Skipping null values from rendering

src/Twig/StimulusTwigExtension.php

@@ -57,6 +57,10 @@ public function renderStimulusController(Environment $env, $dataOrControllerName
             $controllers[] = $controllerName;
 
             foreach ($controllerValues as $key => $value) {
+                if (null === $value) {
+                    continue;
+                }
+
                 if (!is_scalar($value)) {
                     $value = json_encode($value);
                 }