WHY
We currently match AWS logic and perform a 'final snapshot' on GCP but these are retained indefinitely in GCP storage. We could set up a lifecycle for objects to have them deleted after a period of time.

WHAT
Configure the GCP bucket we set up for snapshots with object lifecycle rules https://cloud.google.com/storage/docs/lifecycle

We have to decide on the value to use for this. We could set this as a set period of time + the retention period. For example if the retention period is set to 10d, we could configure the lifecycle on the bucket as 10d + 30d. Depending on the frequency and how recently the latest snapshot was taken this means we would at minimum hold the object for 30d, maximum 40d, after RHOAM is removed.

HOW
Add a new function to the gcpiface storage api to update bucket attributes.

Set a new lifecycle rule in the bucket attributes.

Reconcile this if not configured as part of snapshot reconciler.

TESTS
<List of related tests>

DONE
Snapshot buckets are configured with a object retention lifecycle rule.