CI: do the rebuilds via kaniko.

1 job from ci-changes in 21 seconds (queued for 1 second)
Status Job ID Name Coverage
  Build
failed #241192
build

00:00:21

 
Name Stage Failure
failed
build Build
Fetching changes...
HEAD is now at 316e28e Added README and a LICENSE.
From https://code.videolan.org/videolan/docker-images-aarch64
* [new branch] ci-changes -> origin/ci-changes
Checking out d1a376e3 as ci-changes...
Skipping Git submodules setup
standard_init_linux.go:190: exec user process caused "exec format error"
standard_init_linux.go:190: exec user process caused "exec format error"
ERROR: Job failed: exit code 1