Flake in storage samples; failed precondition

[dbolduc]

https://pantheon.corp.google.com/cloud-build/builds;region=us-central1/2ea95551-e507-4536-af91-ee2348b8fc6b;step=1?project=rust-sdk-testing

failures:
---- tests::object_examples stdout ----
successfully created bucket Bucket { name: "projects/_/buckets/rust-sdk-testing-rcy1ayudc5t1whb63sko7ds005l63chslkfb9iv9bexhv7", bucket_id: "rust-sdk-testing-rcy1ayudc5t1whb63sko7ds005l63chslkfb9iv9bexhv7", etag: "CAE=", project: "projects/1044885715437", metageneration: 1, location: "US", location_type: "multi-region", storage_class: "STANDARD", rpo: "DEFAULT", acl: [], default_object_acl: [], lifecycle: None, create_time: Some(Timestamp { seconds: 1770317152, nanos: 63000000 }), cors: [], update_time: Some(Timestamp { seconds: 1770317152, nanos: 63000000 }), default_event_based_hold: false, labels: {}, website: None, versioning: Some(Versioning { enabled: false }), logging: None, owner: None, encryption: None, billing: None, retention_policy: None, iam_config: Some(IamConfig { uniform_bucket_level_access: Some(UniformBucketLevelAccess { enabled: true, lock_time: Some(Timestamp { seconds: 1778093152, nanos: 63000000 }) }), public_access_prevention: "inherited" }), satisfies_pzs: false, custom_placement_config: None, autoclass: None, hierarchical_namespace: Some(HierarchicalNamespace { enabled: true }), soft_delete_policy: Some(SoftDeletePolicy { retention_duration: Some(Duration { seconds: 604800, nanos: 0 }), effective_time: Some(Timestamp { seconds: 1770317152, nanos: 63266000 }) }), object_retention: None, ip_filter: None }
Error: the service reports an error with code UNKNOWN described as: At least one of the pre-conditions you specified did not hold.
failures:
    tests::object_examples

The logs do not make it easy to see what failed.