Update and unify the `busybox` images on all arches to the `glibc` multi-arch
version and remove the temp workaround on amd64 which uses the old version
busybox (v1.26) before this PR to bypass the failure of those network related
test cases. Also, this PR will fix all the network related issues with `glibc`
version `busybox` image.
Signed-off-by: Dennis Chen <dennis.chen@arm.com>
split all non-cli portions into a new internal/test/environment package
Set a test environment on packages instead of creating new ones.
Signed-off-by: Daniel Nephin <dnephin@docker.com>
