Reduce cost of autoscaler CI

[Gerg]

• Work needed to reduce costs of OSS CI in an effort to make it sustainable for CFF
• See https://cloudfoundry.slack.com/archives/C08SZFRNBUP for CFF-wide cost discussions
• See https://cloudfoundry.slack.com/archives/C02LR0XCV3M/p1747682936927769 for ARI & Autoscaler-specifics
• ARI WG leads (@Gerg or @stephanme ) can help discuss options, for example (copied from Slack):

1. Dynamically deploying cf, instead of using a long-lived environment
2. OR stopping/starting the long-lived environment
3. Using bosh-lites instead of full environments
4. Cleaning up dynamic deployments more aggressively
5. Limiting number of concurrent deployments (e.g. via a concourse pool resource)
6. Restructuring pipeline to run expensive tests less frequently
7. Anything else you think will help

Related to cloudfoundry/community#1187
Similar effort from CAPI: cloudfoundry/capi-ci#134

[silvestre]

As a first step, we are tagging the resources deployed due to our CI, so that orphaned resources can be safely deleted.
Secondly, we will be hibernating the long-lived environment outside of Central European office hours (option 2).

Once this is done we will look at further options.

[geigerj0]

Since 08.07, we are hibernating the VMs from 5pm UTC to 5am UTC, see also #3858.

The cost report from the 08.07 also indicates that less costs occurred 💸🤏. Feel free to message me to get a screenshot of the cost report, I just don't want to post it here.

Shall we close this issue?

[silvestre]

There's a new suggestion from the WG issue:

New optimisation recommendations based on PointFive tooling as discussed during the TOC meeting 8th of July:

account_name	name	recommendations	current_cost	potential_savings	resource_name	resource_id	resource_type	region
App-Runtime-Interfaces-WG	Missing Autoclass on GCS Bucket	Activate Autoclass for this storage bucket.	1.85	1.48	app-autoscaler-releases	//storage.ogleapis.com/projects/_/buckets/app-autoscaler-releases	GCPStorageBucket	europe-west3
App-Runtime-Interfaces-WG	Missing Autoclass on GCS Bucket	Activate Autoclass for this storage bucket.	43.41	34.72	app-autoscaler-oss-blobstore	//storage.ogleapis.com/projects/_/buckets/app-autoscaler-oss-blobstore	GCPStorageBucket	europe-west3

EDIT: I manually activated autoclass. If we don't see any adverse effects until after the next BOSH release of app-autoscaler, we can make this permanent via

app-autoscaler-release/ci/terragrunt/app-autoscaler/oss_gcs_buckets/gcs_buckets.tf

Lines 27 to 39 in f3b05ed

	storage_class = "STANDARD"
	uniform_bucket_level_access = "true"
	}
	resource "google_storage_bucket" "app_autoscaler_releases" {
	name = "app-autoscaler-releases"
	location = var.region
	project = var.project
	default_event_based_hold = "false"
	force_destroy = "false"
	public_access_prevention = "inherited"
	requester_pays = "false"
	storage_class = "STANDARD"