Comment 17 for bug 1768541

With proposed the issue is solved.

Before:

dpkg: error processing archive /var/cache/apt/archives/libp11-kit-gnome-keyring_3.28.0.2-1ubuntu1_all.deb (--unpack):
 libp11-kit-gnome-keyring:all 3.28.0.2-1ubuntu1 (Multi-Arch: no) is not co-installable with libp11-kit-gnome-keyring which has multiple installed instances
Errors were encountered while processing:
 /var/cache/apt/archives/libp11-kit-gnome-keyring_3.28.0.2-1ubuntu1_all.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)

After:

Get:1 http://archive.ubuntu.com/ubuntu bionic-proposed/universe amd64 libp11-kit-gnome-keyring amd64 3.28.0.2-1ubuntu1.18.04.1 [3.228 B]
Fetched 3.228 B in 0s (23,8 kB/s)
(Reading database ... 548794 files and directories currently installed.)
Preparing to unpack .../libp11-kit-gnome-keyring_3.28.0.2-1ubuntu1.18.04.1_amd64.deb ...
Unpacking libp11-kit-gnome-keyring:amd64 (3.28.0.2-1ubuntu1.18.04.1) over (3.20.1-1ubuntu1) ...
Setting up libp11-kit-gnome-keyring:amd64 (3.28.0.2-1ubuntu1.18.04.1) ...