Fixes PHP fatal error when editing users (#6700)

* Update user_edit.php

Some PHP implementations return a fatal error when in_array() has the second parameter null.

 $_SESSION['authentication']['methods']  is null by default on new installations.

core/users/user_edit.php

@@ -145,7 +145,7 @@
 			if (permission_exists('message_key')) {
 				$message_key = $_POST["message_key"];
 			}
-			if (isset($_SESSION['authentication']['methods']) && in_array('totp', $_SESSION['authentication']['methods'])) {
+			if (is_array($_SESSION['authentication']['methods']) && (in_array('totp', $_SESSION['authentication']['methods']))) {
 				$user_totp_secret = strtoupper($_POST["user_totp_secret"]);
 			}
 
@@ -527,7 +527,7 @@
 				if (permission_exists('api_key')) {
 					$array['users'][$x]['api_key'] = ($api_key != '') ? $api_key : null;
 				}
-				if (in_array('totp', $_SESSION['authentication']['methods'])) {
+				if (is_array($_SESSION['authentication']['methods']) && (in_array('totp', $_SESSION['authentication']['methods']))) {
 					$array['users'][$x]['user_totp_secret'] = $user_totp_secret;
 				}
 				$array['users'][$x]['user_enabled'] = $user_enabled;
@@ -1094,7 +1094,7 @@
 	}
 
 	//user time based one time password secret
-	if (in_array('totp', $_SESSION['authentication']['methods'])) {
+	if (is_array($_SESSION['authentication']['methods']) && (in_array('totp', $_SESSION['authentication']['methods']))) {
 		if ($user_totp_secret != '' && $username != '') {
 			$otpauth = "otpauth://totp/".$username."?secret=".$user_totp_secret."&issuer=".$_SESSION['domain_name'];
 
@@ -1225,4 +1225,4 @@
 //include the footer
 	require_once "resources/footer.php";
 
-?>
+?>