Add digest for Qubes OS 4.3.1-rc1

[andrewdavidwong]

QubesOS/qubes-issues#10864

[parulin]

I don't know the process for generating digest files, so maybe it's not the time to fix it, but this issue is still open: QubesOS/qubes-issues#10512

[andrewdavidwong]

I don't know the process for generating digest files, so maybe it's not the time to fix it, but this issue is still open: QubesOS/qubes-issues#10512

Yes, I had the same thought. If it were up to me, this digest would have a detached signature instead of being clearsigned, but it's not up to me, since I don't control the signing keys. I simply observed that this clearsigned 4.3.1-rc1 digest file was generated and uploaded to https://ftp.qubes-os.org/iso/. I then reasoned that, given that the digest exists, it probably doesn't make sense for it be on the FTP server but not in the secpack, so I opened this PR to add it to the secpack for the sake of consistency.

Until I receive information to the contrary, I continue to assume that detached-sig digests are coming in due course and that the security team just needs some more time to implement them.

[marmarek]

QubesOS/qubes-builderv2#247