[v2] Add additional logic to catch potential issues with users using image defaults that don't correspond to the image names in the build.artifacts[].image

Related to https://github.com/GoogleContainerTools/skaffold/issues/6952

This issue tracks adding additional logic to `upgrade.go` for v2beta29 to aid users in catching any errors related to them using image defaults that don't correspond to the image names in the build.artifacts[].image and so their deployments may cease to work. The idea would be to do something like:
- use helm template and then read the rendered manifest
- see if there are any image: in the rendered manifest
- see if there are any images skaffold built that aren't used in the manifest
- perhaps also see if there are any empty image: fields? (values that were empty or possibly misconfigured which will break a deployment)

and error (or warn but most likely error) to alert users of possible issues

EDIT:
Talked with @briandealwis offline who originally thought of adding this functionality, this would be a feature to help users and is not specifically related to upgrading or potential regressions from v2beta29 -> v3alpha1. This is just to help users that currently use the incorrect image tags in their helm charts