fix: don't use DEFAULT_REGION for listBuckets method

src/internal/client.ts

@@ -1480,7 +1480,7 @@ export class TypedClient {
 
   async listBuckets(): Promise<BucketItemFromList[]> {
     const method = 'GET'
-    const httpRes = await this.makeRequestAsync({ method }, '', [200], DEFAULT_REGION)
+    const httpRes = await this.makeRequestAsync({ method }, '', [200], this.region ?? '')
     const xmlResult = await readAsString(httpRes)
     return xmlParsers.parseListBucket(xmlResult)
   }