[GCP] Automate the GCP publishing step after building the GCP image

[alallema]

Description
Create an Issue for GCP to transform the image to Bucket
Currently, the packer script will create an image of the release. The goal is to add the missing part who is convert it to a bucket to allow users to use it.

See the GCP doc on it: export a custom image to Cloud Storage

[brunoocasali]

I'm not sure why we need this @alallema, can you give me more info?

[alallema]

If you follow the documentation for deploying a Meilisearch image on GCP, you'll need the vmdk address.
In doing so, our GCP script only creates one image and does not go as far as the step that transforms this image into a public vmdk for contributors.

[pappes]

can confirm, the instructions in the gcp cookbook just don't work
https://www.meilisearch.com/docs/learn/cookbooks/gcp