Adds util for creation unstable cache.

www/utils/unstableCache.ts

@@ -0,0 +1,16 @@
+import { cache } from 'react';
+import { unstable_cache as next_unstable_cache } from 'next/cache';
+
+export const unstable_cache = <Args extends any[], Output>(
+    callback: (...args: Args) => Promise<Output>,
+    key: string[],
+    options: { revalidate: number },
+  ) => {
+    return cache(
+      next_unstable_cache(
+        callback as unknown as (...args: any[]) => Promise<Output>,
+        key,
+        options
+      )
+    );
+  };