fix: Get command should return server error instead of timeout error

[weichou1229]

Set the default AppCustom.RequestTimeout config to 4 (less than the service request tmieout). Then, the service can reply the proper error content in the response.

Close #256

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PR Checklist

Please check if your PR fulfills the following requirements:

• [x] I am not introducing a breaking change (if you are, flag in conventional commit message with BREAKING CHANGE: describing the break)
• [x] I am not introducing a new dependency (add notes below if you are)
• [ ] I have added unit tests for the new feature or bug fix (if not, why?) not impact
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Testing Instructions

Run core service and device service to check the command should return server error instead of timeout error

New Dependency Instructions (If applicable)