MDL-72720 plugininfo: Add enable_plugin() method to base class

lib/classes/plugininfo/base.php

@@ -79,6 +79,20 @@ public static function get_enabled_plugins() {
         return null;
     }
 
+    /**
+     * Enable or disable a plugin.
+     * When possible, the change will be stored into the config_log table, to let admins check when/who has modified it.
+     *
+     * @param string $pluginname The plugin name to enable/disable.
+     * @param int $enabled Whether the pluginname should be enabled (1) or not (0). This is an integer because some plugins, such
+     * as filters or repositories, might support more statuses than just enabled/disabled.
+     *
+     * @return bool Whether $pluginname has been updated or not.
+     */
+    public static function enable_plugin(string $pluginname, int $enabled): bool {
+        return false;
+    }
+
     /**
      * Gathers and returns the information about all plugins of the given type,
      * either on disk or previously installed.

lib/upgrade.txt

@@ -106,6 +106,9 @@ completely removed from Moodle core too.
 * Require pass grade criteria is now part of core.
   Refer to upgrade.php to see transitioning from similar plugin criteria to core
   Refer to completion/upgrade.txt for additional information.
+* The method enable_plugin() has been added to the core_plugininfo\base class and it has been implemented by all the plugininfo
+classes extending it. When possible, the enable_plugin() method will store these changes into the config_log table, to let admins
+check when and who has enabled/disabled plugins.
 
 === 3.11.2 ===
 * For security reasons, filelib has been updated so all requests now use emulated redirects.