fix bugs in php 8.1 changes (#6744)

* Update voicemail_greetings.php

* Update recordings.php

* Update recording_edit.php

* Update phrases.php

* Update phrase_edit.php

* Update music_on_hold_edit.php

* Update fax_queue.php

* Update extensions.php

* Update email_templates.php

* Update email_queue_edit.php

* Update dialplan_inbound_add.php

* Update device_profiles.php

* Update device_profile_copy.php

* Update contact_address_edit.php

* Update call_recordings.php

* Update call_center_agent_edit.php

* Update call_center_agents.php

* Update call_center_queues.php

* Update call_block.php

* Update menu_edit.php

* Update default_setting_edit.php

* Update database_edit.php

app/call_centers/call_center_agent_edit.php

@@ -52,7 +52,7 @@
 	$agent_password = '';
 
 //check for duplicates
-	if (!empty($_GET["check"]) == 'duplicate') {
+	if (!empty($_GET["check"]) && $_GET["check"] == 'duplicate') {
 		//agent id
 			if (!empty($_GET["agent_id"])) {
 				$sql = "select agent_name ";
@@ -610,4 +610,4 @@
 //include the footer
 	require_once "resources/footer.php";
 
-?>
+?>