Thanks for the reply.
I have downloaded the tool and try the "Verify signature" action, however it seems the validation failed.
The tool shows below message:
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Signature status: invalid
Digest status: valid
Identity status: invalid
Reference status: unknown
Signing certificate information only available for valid certificates.
Manifest only validated when signature references are valid.
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As I am not so familiar to plugin, please kindly help on the above issue. Thank you very much !!