* variant: move into internal/attestation
* attesation: move aws attesation into subfolder nitrotpm
* config: add aws-sev-snp variant
* cli: add tf option to enable AWS SNP
For now the implementations in aws/nitrotpm and aws/snp
are identical. They both contain the aws/nitrotpm impl.
A separate commit will add the actual attestation logic.
* rename to attestationconfigapi + put client and fetcher inside pkg
* rename api/version to versionsapi and put fetcher + client inside pkg
* rename AttestationConfigAPIFetcher to Fetcher
* api: rename AttestationVersionRepo to Client
* api: move client into separate subpkg for
clearer import paths.
* api: rename configapi -> attestationconfig
* api: rename versionsapi -> versions
* api: rename sut to client
* api: split versionsapi client and make it public
* api: split versionapi fetcher and make it public
* config: move attestationversion type to config
* api: fix attestationconfig client test
Co-authored-by: Adrian Stobbe <stobbe.adrian@gmail.com>