[BUGFIX] Transform ISO code of countries to its name in EXT:form

Using a country select field in EXT:form should always show the
name of the country and not its ISO2 code.

Resolves: #102348
Releases: main, 13.4
Change-Id: I359e37281e2b62b3083cbd2c25ef417ec43aea69
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/84855
Tested-by: core-ci <typo3@b13.com>
Tested-by: Oliver Bartsch <bo@cedev.de>
Reviewed-by: Benni Mack <benni@typo3.org>
Reviewed-by: Oliver Bartsch <bo@cedev.de>
Tested-by: Benni Mack <benni@typo3.org>

Author: georgringer

typo3/sysext/form/Classes/ViewHelpers/RenderFormValueViewHelper.php

@@ -21,7 +21,9 @@
 
 namespace TYPO3\CMS\Form\ViewHelpers;
 
+use TYPO3\CMS\Core\Country\CountryProvider;
 use TYPO3\CMS\Core\Resource\File;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
 use TYPO3\CMS\Extbase\Domain\Model\FileReference;
 use TYPO3\CMS\Form\Domain\Model\FormElements\FormElementInterface;
 use TYPO3\CMS\Form\Domain\Model\FormElements\StringableFormElementInterface;
@@ -96,6 +98,12 @@ protected function processElementValue(
     ) {
         $properties = $element->getProperties();
         $options = $properties['options'] ?? null;
+        if ($element->getType() === 'CountrySelect') {
+            $country = GeneralUtility::makeInstance(CountryProvider::class)->getByIsoCode($value);
+            if ($country !== null) {
+                return $country->getName();
+            }
+        }
         if (is_array($options)) {
             $options = (array)$this->renderingContext->getViewHelperInvoker()->invoke(
                 TranslateElementPropertyViewHelper::class,