fix: add unique representation for multiple plugin instances

Author: yaroslav8765

index.ts

@@ -42,7 +42,7 @@ export default class  extends AdminForthPlugin {
   instanceUniqueRepresentation(pluginOptions: any) : string {
     // optional method to return unique string representation of plugin instance. 
     // Needed if plugin can have multiple instances on one resource 
-    return `single`;
+    return `${this.resourceConfig.resourceId}-quick-filters`;
   }
 
 }