refactor(terraform): migrate worker gke to osv_pipeline module

[michaelkedar]

• Removed worker-pool / worker-pool-temp node pools and tolerations. Workers now run on default-pool.
• Extracted Datastore, GCS export/backup buckets, GKE worker cluster, networkin, and Pub/Sub task queues from modules/osv into modules/osv_pipeline for oss-vdb and oss-vdb-test.
  • Added moved blocks in both environments to migrate without having to recreate resources.
• Node pools in osv_pipeline now run with dedicated osv-worker service account, which should have only the permissions it actually needs (instead of, like, editor).
  • Changing service accounts requires recreating node pools 😞

Might make a new service account for the oss-fuzz workers, but I need to look into whether they also need more permissions or not.

[michaelkedar]

The terraform plan check is worth reviewing, but it looks fine to me