docs: Add --entrypoint /bin/bash to docker run commands for serving-xpu image

[liu-shaojun]

Description

This PR modifies the documentation for launching the serving-xpu Docker container to include --entrypoint /bin/bash in the docker run command.

1. Why the change?

2. User API changes

3. Summary of the change

4. How to test?

• N/A
• Unit test: Please manually trigger the PR Validation here by inputting the PR number (e.g., 1234). And paste your action link here once it has been successfully finished.
• Application test
• Document test
• ...

5. New dependencies

• New Python dependencies
  - Dependency1
  - Dependency2
  - ...
• New Java/Scala dependencies and their license
  - Dependency1 and license1
  - Dependency2 and license2
  - ...