MDL-77350 auth: Added class properties that are not declared

In PHP 8.2 and later, setting a value to an undeclared class property is
deprecated and emits a deprecation notice.
So we need to add missing class properties that still need to be declared.

auth/email/tests/external/external_test.php

@@ -45,6 +45,12 @@ require_once($CFG->dirroot . '/webservice/tests/helpers.php');
  */
 class external_test extends externallib_advanced_testcase {
 
+    /** @var int custom profile field1 ID. */
+    protected $field1;
+
+    /** @var int custom profile field2 ID. */
+    protected $field2;
+
     /**
      * Set up for every test
      */

auth/ldap/auth.php

@@ -86,6 +86,18 @@ require_once($CFG->dirroot.'/auth/ldap/locallib.php');
  */
 class auth_plugin_ldap extends auth_plugin_base {
 
+    /** @var string */
+    protected $roleauth;
+
+    /** @var string */
+    public $pluginconfig;
+
+    /** @var LDAP\Connection LDAP connection. */
+    protected $ldapconnection;
+
+    /** @var int */
+    protected $ldapconns = 0;
+
     /**
      * Init plugin config from database settings depending on the plugin auth type.
      */

auth/mnet/auth.php

@@ -32,6 +32,9 @@ require_once($CFG->libdir.'/authlib.php');
  */
 class auth_plugin_mnet extends auth_plugin_base {
 
+    /** @var mnet_environment mnet environment. */
+    protected $mnet;
+
     /**
      * Constructor.
      */