Add support for GCP Federation #74
Description
Authenticating to GCP now supports various types of federation from AWS, Azure and generic oidc providers.
Basically, a customer can run this fluentd plugin in any of those enviornments without having to download and distriubte a service account credential file...i.,e they can just use the ambient credentisl they have already.
this specific feature is detailed here:
- https://cloud.google.com/iam/docs/access-resources-aws#generate
- https://cloud.google.com/iam/docs/access-resources-oidc#generate
i've got a couple of live samples here for aws and generic oidc
happy to help with the gcp integration side but i don't really know ruby