Fix s3 sync error

[gersur]

The s3 sync parameter, "$sync_cmd" should be at the end
I also added log of the command executed.

Reference: https://docs.aws.amazon.com/cli/latest/reference/s3/sync.html#examples

aws s3 sync s3://my-us-west-2-bucket s3://my-us-east-1-bucket \
    --source-region us-west-2 \
    --region us-east-1

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Sidenote: I've pull this repo because I use this image for my raspberry pi 4, but it doesn't have compatible image for arm64.
Then I built it from my raspberry pi 4, try to config it again, but it always have error because the destination parameter on the wrong place

[github-actions]

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