Updated images for Apple M1 support.

[AlexSkrypnyk]

AIO has already published images with multi-architecture support, but they published them in uselagoon DockerHub namespace (they usually double-publish them in amazeeio and uselagoon namespaces; amazeeio is deprecated now).

Changed

1. Switched images to uselagoon namespace and update to the latest version.
2. Fixed check for existence of the custom scripts (due to an upstream bug in Alpine bash under alpine:edge failed in testing file writable alpinelinux/docker-alpine#156).