chore: switch to using gh container registry in manifests

[HumairAK]

Description of your changes:

This change switches majority of the images coming from gcr repository to the ghcr repository. For this, various manifests were updated, as well as the hardcoded launcher/driver images. All images that are regularly updated during the release process have been switched over to ghcr.

Note: I will follow up with updates to release instructions once we are done with the 2.4 release.

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[HumairAK]

There is a bit of a chicken and egg problem with the driver/launcher images. I built the images from the release-2.4.0 branch which has not gone out yet, but will do so once this change is cherry-picked into that branch, and the release workflow is initiated. But before that, the api server image will need to be rebuilt on the 2.4.0 tag so that the hardcoded launcher/driver images make it into the apiserver. This should be fine to do since we have officially released anything. But in the future it would be good to add these images via manifests (env vars) and update them part of the regular release process, as we do the other images in yaml. For default hardcoded values, we can just either not use defaults and throw an error, or point to latest.

[HumairAK]

Cc @chensun

[rimolive]

/lgtm

[google-oss-prow]

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