added memory leak warning

src/misc/sequentialize.ts

@@ -5,6 +5,8 @@
  * be returned, instead of calling the original function again
  *
  * Results are not cached, once the promise has returned, the next call will result in a fresh call
+ *
+ * WARNING: The decorator's scope is singleton, so using it on transient objects can lead to memory leaks.
  */
 export function sequentialize(cacheKey: (args: any[]) => string) {
     return (target: any, propertyKey: string | symbol, descriptor: PropertyDescriptor) => {