TranslationInfoOfConstraintViolation: add type hint for $key in remov…

…eCurlyBraces

Else psalm fails with:
ERROR: InvalidReturnType - src/Serializer/Normalizer/Error/TranslationInfoOfConstraintViolation.php:20:21 - The declared return type 'array<string, mixed>' for App\Serializer\Normalizer\Error\TranslationInfoOfConstraintViolation::removeCurlyBraces is incorrect, got 'array<array<array-key, string>|string, mixed>' (see https://psalm.dev/011)
    * @psalm-return array<string, mixed>

api/src/Serializer/Normalizer/Error/TranslationInfoOfConstraintViolation.php

@@ -18,6 +18,7 @@ public function extract(ConstraintViolation $constraintViolation): TranslationIn
     public static function removeCurlyBraces(array $parameters): array {
         $paramsWithoutCurlyBraces = [];
         foreach ($parameters as $key => $value) {
+            /** @var int|string $key */
             $key = str_replace('{{ ', '', $key);
             $key = str_replace(' }}', '', $key);
             $paramsWithoutCurlyBraces[$key] = $value;