fix(cache): fix ttl cache update method (JhaSourav07#2196)

## Summary

Fixes an issue where `TTLCache.update()` returned `false` for expired
entries but did not remove them from the internal cache store.

## Changes Made

* Added immediate cleanup of expired entries inside `update()`.
* Deletes the expired key from `this.store` before returning `false`.
* Keeps behavior consistent with `get()` and `has()`, which already
remove expired entries when encountered.

## Expected Result

Expired cache entries are no longer left in memory after calling
`update()`, reducing stale data retention and ensuring consistent cache
behavior.

Fixes JhaSourav07#1879

Author: vbarik317-droid

lib/cache.ts

@@ -146,10 +146,17 @@ export class TTLCache<T> {
    * @returns `true` if the entry existed and was updated, `false` if missing or expired.
    */
   update(key: string, value: T): boolean {
-    TTLCache.assertValidKey(key);
-
     const hit = this.store.get(key);
-    if (!hit || Date.now() > hit.expiresAt) return false;
+
+    if (!hit) {
+      return false;
+    }
+
+    if (Date.now() > hit.expiresAt) {
+      this.store.delete(key);
+      return false;
+    }
+
     hit.value = value;
     return true;
   }