PHP 8.2 Compatibility

I wrote the following patch to remove the “Deprecated: Creation of dynamic property” warnings when running under PHP 8.2.

diff --git a/c2c-plugin.php b/c2c-plugin.php
index dee9b6c..cda2342 100644
--- a/c2c-plugin.php
+++ b/c2c-plugin.php
@@ -59,6 +59,28 @@ abstract class C2C_Plugin_039 {

        private   $setting_index      = 0;

+    protected $admin_options_name;
+    protected $config;
+    protected $disable_contextual_help;
+    protected $disable_update_check;
+    protected $hook_prefix;
+    protected $form_name;
+    protected $menu_name;
+    protected $name;
+    protected $nonce_field;
+    protected $settings_page;
+    protected $show_admin;
+    protected $textdomain;
+    protected $textdomain_subdir;
+    protected $author_prefix;
+    protected $id_base;
+    protected $options_page;
+    protected $plugin_basename;
+    protected $plugin_file;
+    protected $plugin_path;
+    protected $u_id_base;
+    protected $version;
+
        /**
         * Handles installation tasks, such as ensuring plugin options are instantiated and saved to options table.
         *