samples(storage): create HNS bucket sample

[tritone]

Adds a sample to create a bucket with HierachicalNamespace features enabled.

Also updates library dep to storage/v1.42.0 to pick up new feature.

Updates googleapis/google-cloud-go#10294

Checklist

• I have followed Contributing Guidelines from CONTRIBUTING.MD
• Tests pass: go test -v ./.. (see Testing)
• Code formatted: gofmt (see Formatting)
• Vetting pass: go vet (see Formatting)
• These samples need a new API enabled in testing projects to pass (let us know which ones)
• These samples need a new/updated env vars in testing projects set to pass (let us know which ones)
• This sample adds a new sample directory, and I updated the CODEOWNERS file with the codeowners for this sample
• This sample adds a new Product API, and I updated the Blunderbuss issue/PR auto-assigner with the codeowners for this sample
• Please merge this PR for me once it is approved

[snippet-bot]

Here is the summary of changes.

You are about to add 1 region tag.

• storage/buckets/create_bucket_hierarchical_namespace.go:17, tag storage_create_bucket_hierarchical_namespace

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