Downloading: http://repo.aptly.info/system-tests/archive.debian.org/debian-archive/debian/dists/stretch-backports/InRelease

gpgv: Signature made Thu Mar 30 14:21:34 2023 UTC
gpgv:                using RSA key 0146DC6D4A0B2914BDED34DB648ACFD622F3D138

gpgv: Signature made Thu Mar 30 14:22:13 2023 UTC
gpgv:                using RSA key A7236886F3CCCAAD148A27F80E98404D386FA1D9

Downloading: http://repo.aptly.info/system-tests/archive.debian.org/debian-archive/debian/dists/stretch-backports/Release
Downloading: http://repo.aptly.info/system-tests/archive.debian.org/debian-archive/debian/dists/stretch-backports/Release.gpg

gpgv: Signature made Thu Mar 30 14:20:54 2023 UTC
gpgv:                using RSA key 0146DC6D4A0B2914BDED34DB648ACFD622F3D138

gpgv: Signature made Thu Mar 30 14:21:30 2023 UTC
gpgv:                using RSA key A7236886F3CCCAAD148A27F80E98404D386FA1D9

ERROR: unable to fetch mirror: verification of detached signature failed: exit status 2