[Storage Account] Fix for issue #59323

[Minghao Chen (HarveyLink)]

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[Copilot]

Pull request overview

This PR addresses issue #59323 in Azure.ResourceManager.Storage by making StorageAccountResourceAccessRule.TenantId deserialization tolerant of empty/whitespace/invalid GUID strings returned by the service, preventing GET/list operations from failing due to malformed tenantId values.

Changes:

• Added a TypeSpec customization deserialization hook to safely parse tenantId into Guid? (fallback to null on invalid input).
• Updated generated model deserialization to use the new hook.
• Added NUnit tests covering valid/empty/whitespace/null/invalid tenantId JSON inputs and documented the fix in the changelog.

Reviewed changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated no comments.

File	Description
sdk/storage/Azure.ResourceManager.Storage/tests/Tests/StorageAccountResourceAccessRuleSerializationTests.cs	Adds coverage to ensure deserialization is tolerant to empty/invalid tenantId values.
sdk/storage/Azure.ResourceManager.Storage/src/Generated/Models/StorageAccountResourceAccessRule.Serialization.cs	Switches tenantId parsing to the customization hook to avoid exceptions on malformed values.
sdk/storage/Azure.ResourceManager.Storage/src/Customize/Models/StorageAccountResourceAccessRule.cs	Introduces DeserializeNullableGuid hook via CodeGenSerialization to safely parse tenantId.
sdk/storage/Azure.ResourceManager.Storage/CHANGELOG.md	Records the bug fix under the current unreleased version.

[Dapeng Zhang (ArcturusZhang)]

Emm this change would cause the SDK to omit the value returned by the service if it is not really a guid.
Given the property name tenantId, I think we could be confident that this is a case that the service returns an empty string here, not returning some random string values.
If it is the later case, this fix is not quite good and instead we should create a new property with string type to hold the real value.

Anyhow, this LGTM

[Wei Wei (blueww)]

LGTM
The fix is aligned with another fix for same GUID parse issue before #56904. That fix works well for customer and don't take an regression customer issue.