ignore mail params with empty data in csv export (#465)

Author: solverat

UPGRADE.md

@@ -4,6 +4,7 @@
 - **[SECURITY FEATURE]** Add [friendly captcha field](/docs/03_SpamProtection.md#friendly-captcha)
 - **[SECURITY FEATURE]** Add [cloudflare turnstile](/docs/03_SpamProtection.md#cloudflare-turnstile)
 - **[BUGFIX]** Use Pimcore AdminUserTranslator for Editable Dialog Box [#450](https://github.com/dachcom-digital/pimcore-formbuilder/issues/450)
+- **[BUGFIX]** CSV Export: Ignore mail params with empty data [#461](https://github.com/dachcom-digital/pimcore-formbuilder/issues/461)
 - **[IMPROVEMENT]** Improve json response success message behaviour [#416](https://github.com/dachcom-digital/pimcore-formbuilder/issues/416)
 - **[IMPROVEMENT]** [#458](https://github.com/dachcom-digital/pimcore-formbuilder/pull/458)
   - Allow to modify FormType options via `FORM_TYPE_OPTIONS` event

src/Controller/Admin/ExportController.php

@@ -229,6 +229,10 @@ private function extractMailParams(Email\Log $log, FormDefinitionInterface $form
                 }
             }
 
+            if (!array_key_exists('data', $mailParam)) {
+                continue;
+            }
+
             if (!in_array($displayKeyName, $mailHeader, true)) {
                 $mailHeader[] = $displayKeyName;
             }