tests/docker: don't use BUILDKIT in GitLab either
Using BUILDKIT breaks with certain container registries such as CentOS,
with docker build reporting an error such as
failed to solve with frontend dockerfile.v0:
failed to build LLB: failed to load cache key:
unexpected status code
https://registry.centos.org/v2/centos/manifests/7:
403 Forbidden
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Willian Rampazzo <willianr@redhat.com>
Message-Id: <
20210623142245.307776-3-berrange@redhat.com>
Message-Id: <
20210709143005.1554-11-alex.bennee@linaro.org>