MDL-71252 completion: Avoid showing the 'Mark as done' button

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completion/classes/activity_custom_completion.php

@@ -138,6 +138,17 @@ abstract class activity_custom_completion {
         return $descriptions[$rule];
     }
 
+    /**
+     * Show the manual completion or not regardless of the course's showcompletionconditions setting.
+     * Returns false by default for plugins that don't need to override the course's showcompletionconditions setting.
+     * Activity plugins that need to always show manual completion need to override this function.
+     *
+     * @return bool
+     */
+    public function manual_completion_always_shown(): bool {
+        return false;
+    }
+
     /**
      * Fetches the module's custom completion class implementation if it's available.
      *