[ZSvirt] bug: sdk: fix missing bracket in internal error message

[chayu163]

Component

zsvirt

Problem description

In ZSClient.pollResult, when a polling URL is missing, the thrown message starts with "Internal Error]" — missing
the opening [. The sibling message above it correctly reads "[Internal Error] ...".

Steps to reproduce

1. Call any async API whose server response omits the polling location URL.
2. Observe the thrown error message begins with "Internal Error]" (no leading [).

Expected behavior

The message reads "[Internal Error] the api[...] is an async API but the server doesn't return the polling location url".

Environment

No response

Logs or screenshots

No response