APP-6720 in cli module download cmd, show options when platform not found

[abe-winter]

What changed

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Why

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Example output

Error output ('available platforms' on last line is new):

$ viam module download 
Info: Using "http://localhost:8080" as base URL value
Info: found version 0.0.4
Info: using current system platform linux/amd64
Error: Platform linux/amd64 not present for version 0.0.4. available platforms: linux/arm64-distro-debian

Success output:

$ viam module download --platform linux/arm64-distro-debian
Info: Using "http://localhost:8080" as base URL value
Info: found version 0.0.4
Info: saving to 0.0.4-linux-arm64-distro-debian/awinter-package-delete-test.tar.gz