GCS backend only allows short lived token

[Critical-Impact]

Description

At present when specifying a GCS bucket as the backend, you have the ability to set the following

1. projectIDSecretRef
2. accessTokenSecretRef
3. bucket

This appears to set GOOGLE_ACCESS_TOKEN on the restic side which is a short lived token. This is a problem if you create a schedule as the short lived token would expire.

Additional Context

No response

Logs

No response

Expected Behavior

Would it be possible to either specify a GOOGLE_ACCESS_TOKEN or GOOGLE_APPLICATION_CREDENTIALS when using GCS? As far as I can see this is supported natively by restic https://restic.readthedocs.io/en/latest/030_preparing_a_new_repo.html#google-cloud-storage

So you'd have

1. projectIDSecretRef
2. accessTokenSecretRef
3. applicationCredentialsSecretRef
4. bucket

Steps To Reproduce

No response

Version of K8up

2.7.2

Version of Kubernetes

v1.26.13-gke.1052000

Distribution of Kubernetes

GKE