* Allow attestation download to handle both bundle types.
As suggested on https://github.com/sigstore/cosign/issues/4573
* Do not error out if no old attestations are found to download
* Update e2e test to actually check download attestation output
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(cherry picked from commit c0edaac063)
Signed-off-by: Zach Steindler <steiza@github.com>
Co-authored-by: Zach Steindler <steiza@github.com>