[BUGFIX] Trim default register template subject values

Classes/Service/MailTemplateService.php

@@ -328,14 +328,15 @@ class MailTemplateService {
 
 		if (NULL === $defaultTemplateContent) {
 			$emailView->setTemplateSource($template->getContent());
-			$subject = $template->getSubject();
+			$subject = trim($template->getSubject());
 		} else {
 			$emailView->setTemplateSource($defaultTemplateContent);
 
 			$subject = self::getRegisterArray()[$this->extensionKey][$this->templateName]['subject'];
 			if (is_array($subject)) {
-				$subject = self::getRegisterArray(
-				)[$this->extensionKey][$this->templateName]['subject'][$this->language];
+				$subject = trim(
+					self::getRegisterArray()[$this->extensionKey][$this->templateName]['subject'][$this->language]
+				);
 			}
 		}