[BUGFIX] Fix send button url in mail queue

Resources/Private/Templates/Queue/Index.html

@@ -91,7 +91,7 @@
 												<f:link.action class="btn btn-default btn-send-now"
 															   controller="Queue"
 															   action="sendMail"
-															   arguments="{mail: mail, selectedTemplate: selectedTemplateKey, selectedExtension: selectedExtensionKey}">
+															   arguments="{mail: mail.uid, selectedTemplate: selectedTemplateKey, selectedExtension: selectedExtensionKey}">
 													<core:icon identifier="actions-document-import-t3d"/>
 													<f:translate key="backend.send_now"/>
 												</f:link.action>