ci: add mooncake for test-on-main

[Young-Flash]

cc @lijunchen

[peter-jerry-ye-code-review]

Based on the provided git diff output, here are three observations and suggestions:

1. Missing Execution Permission for mooncake:

   • The diff shows that mooncake is being downloaded for both Linux and Windows, but the execution permission is only set for Linux (chmod +x ~/.moon/bin/moon*). Ensure that the execution permission is also set for Windows, although Windows does not use chmod. It might be worth adding a note or a separate command for setting the execution permission on Windows if such a concept exists in PowerShell.

2. Potential Typos in URLs:

   • Ensure that the URLs used for downloading moonrun and mooncake are correct and accessible. There are no direct typos in the provided diff, but always double-check URLs in scripts to avoid runtime errors due to unreachable resources.

3. Consistency in Directory Creation:

   • The script creates directories using mkdir -p ~/.moon/lib for Linux and New-Item -ItemType Directory -Force -Path "$env:USERPROFILE/.moon/lib" for Windows. While both methods are correct, ensure that the paths and methods used across different operating systems are consistent to reduce confusion and potential errors.

These suggestions are based on the provided diff and aim to improve the robustness and consistency of the script across different operating systems.