Revise auth in WASBHook to use explicit credentials

[uranusjr]

The previous approach of using a token suffix in the URL seems to have been broken in the latest azure-storage-blob (12.30.0, released on 8 Jun 2026). This switched the hook to use the more canonical approach to provide the credential with an argument to the service client instead, which should work both before and after the version.

This should fix recent CI failures in provider compat jobs.

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[FrankYang0529]

Hi @uranusjr, I have another PR also focuses on the same topic #68490 and CI passes.

Based on @Lee-W's comment, using AzureSasCredential is a good approach, I will try to use it in my PR to fix the error. Thank you.