Scott French authored Apr 26, 2024 and Ahmon Dancy committed Apr 26, 2024

This adds the --k8s-confirm-diffs flag, which if specified will make
scap collect and display helmfile diffs and await confirmation before
proceeding with deployment.

This review happens early, before operations with side effects (e.g.,
image build). This comes at the expense of a longer window during which
an unexpected helmfile or chart change can sneak in.

Since the loop over deployment datacenters and configs is identical to
that in _deploy_to_datacenters, the inner part of the latter has been
abstracted out (_foreach_datacenter_and_deployment) and is reused in
both the diff and apply context.

Bug: T362717