Decouple Skaffold from `gcloud` CLI

[renzodavid9]

Expected behavior

Be able to run Skaffold without having gcloud CLI installed.

Actual behavior

For some of its operations, Skaffold invokes gcloud to interact with GCP services or to get an auth token, creating a dependency with it.

Information

Some of the places where the integration/dependency was detected:

• Cloud Run, access to service and logs streaming
• gcloud authenticator when using go-containerregistry for some interactions with private repos
• Interacting with private registries using the docker api, in some places we get the credentials using the docker-credential helpers, which could be using docker-credential-gcloud
• Fetching GCS remote config dependencies
• Storing render results in GCS bucket

Skaffold version: v2.12.0