Reimplement security checks for the download endpoint. #2
Description
I disabled the security check on the download endpoint so that it no longer checks for any cryptographic signature. This will be in place to make the prototype work until we have implemented the hypervault-id, which should basically encapsulate a 2048-bit RSA key pair together with the Composer Business Network card. The key pair in the network card does not work because it has a really small key size.
Once the hypervault-id has been implemented, commit ae97d01b70947d9f0d56ca699a9aabe3d9300957 should be reverted.