Published arm64 deb package contains amd64 binary

[alanraison]

What happened?

I tried to install the up cli using the published deb package from https://cli.upbound.io/stable/v0.18.0/deb/linux_arm64/up.deb but apt reported an error:

# apt install ./up.deb
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
Note, selecting 'up:amd64' instead of './up.deb'
The following NEW packages will be installed:
  up:amd64
0 upgraded, 1 newly installed, 0 to remove and 5 not upgraded.
Need to get 0 B/21.0 MB of archives.
After this operation, 64.7 MB of additional disk space will be used.
Get:1 /tmp/up.deb up amd64 0.18.0 [21.0 MB]
debconf: delaying package configuration, since apt-utils is not installed
dpkg: error processing archive /tmp/up.deb (--unpack):
 package architecture (amd64) does not match system (arm64)
Errors were encountered while processing:
 /tmp/up.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)

Having extracted the binary with dpkg-deb --extract it is definitely the wrong architecture (x86-64 instead of aarch64):

up: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), statically linked, Go BuildID=jw1C-ti16ulmBozCWP4w/4zHcrZyRACBqVbOMHZy7/c9p1CJWbMjxHMgaIl_6z/bjhf-BMpaq2EsTp8Jupy, stripped

What environment did it happen in?

I tested this in a debian:bookworm container.

Notes

The tar.gz bundle was the correct architecture (https://cli.upbound.io/stable/v0.18.0/bundle/up/linux_arm64.tar.gz)