Trufflehog does not work on arm64 systems

[Rahul Vivek Nair]

When deploying to an arm64 server like those on oracle cloud, the trufflehog container does not work as it is pulling a hardcoded amd64 linux image in the dockerfile.trufflehog from github.

This can be fixed by pulling the correct architecture from the release page based on the system architecture.

[_rs]

Thanks for your contribution, pull request #2 merged!