bug#28810: Bayfront https file URLs trigger gnutls error

[Maxim Cournoyer]

Hello,

I recently stumbled upon the following:

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guix download 
"https://bayfront.guixsd.org/file/nnn-1.3.tar.gz/sha256/0sivgcmg3hihz15v2wgbxnd0icn06pyvvqdqh8x0mwkhvm434fpb";

Starting download of /tmp/guix-file.h3ueYx
>From 
>https://bayfront.guixsd.org/file/nnn-1.3.tar.gz/sha256/0sivgcmg3hihz15v2wgbxnd0icn06pyvvqdqh8x0mwkhvm434fpb...
ERROR: Throw to key `gnutls-error' with args `(#<gnutls-error-enum An 
unimplemented or disabled feature has been requested.> 
peer-certificate-status)'.
failed to download "/tmp/guix-file.h3ueYx" from 
"https://bayfront.guixsd.org/file/nnn-1.3.tar.gz/sha256/0sivgcmg3hihz15v2wgbxnd0icn06pyvvqdqh8x0mwkhvm434fpb";
guix download: error:
https://bayfront.guixsd.org/file/nnn-1.3.tar.gz/sha256/0sivgcmg3hihz15v2wgbxnd0icn06pyvvqdqh8x0mwkhvm434fpb:
download failed
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For other substitute servers such as berlin, it works as expected:

--8<---------------cut here---------------start------------->8---
guix download 
"https://berlin.guixsd.org/file/nnn-1.3.tar.gz/sha256/0sivgcmg3hihz15v2wgbxnd0icn06pyvvqdqh8x0mwkhvm434fpb";

Starting download of /tmp/guix-file.Vrr8fE
>From 
>https://berlin.guixsd.org/file/nnn-1.3.tar.gz/sha256/0sivgcmg3hihz15v2wgbxnd0icn06pyvvqdqh8x0mwkhvm434fpb...
 …n06pyvvqdqh8x0mwkhvm434fpb  30KiB                     4.1MiB/s 00:00 
[####################] 100.0%
/gnu/store/7zs4s23a5wwp7cpiaqxhrnkbv3bb5w3k-0sivgcmg3hihz15v2wgbxnd0icn06pyvvqdqh8x0mwkhvm434fpb
0sivgcmg3hihz15v2wgbxnd0icn06pyvvqdqh8x0mwkhvm434fpb
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Maxim