There is some confusion, here, apparently.
The addon is building its own docker image, and this is the step where it’s failing.
OP, I assume the host is a RPI in 32bits.
There is a known issue in this setup as of alpine 3.13. HA currently uses 3.14.
To fix, you have to update libseccomp2 on the RPI host, to a version which is not available in the standard repos. You have to:
# Get signing keys to verify the new packages, otherwise they will not install
$ sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 04EE7237B7D453EC 648ACFD622F3D138
# Add the Buster backport repository to apt sources.list
$ echo 'deb http://httpredir.debian.org/debian buster-backports main contrib non-free' | sudo tee -a /etc/apt/sources.list.d/debian-backports.list
$ sudo apt update
$ sudo apt install libseccomp2 -t buster-backports
Then retry the addon installation