mock-server for integration testing

## Why you need it?
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https://github.com/seata/seata/runs/7245096482?check_suite_focus=true

## How it could be?
A clear and concise description of what you want to happen. You can explain more about input of the feature, and output of it.

## Other related information
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The issue names no files, tests, or entry points; it only links a GitHub Actions run and an image. Start by clarifying the mock server's required behavior, integration-test scope, and expected completion criteria before locating the relevant code and tests.

Written by the indexing model from the issue text.