add service name in metadata and fix tests.yml

[amber-yujueWang]

Description

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[Copilot]

Pull request overview

This PR makes two changes to the azure-ai-transcription package: fixes the Azure Pipelines configuration structure in tests.yml by changing from stages: to extends:, and adds a service_name field to the _metadata.json file to specify "Cognitive Services".

• Corrected tests.yml to use extends: instead of stages:, aligning with Azure Pipelines best practices
• Added service_name metadata field to identify the service as "Cognitive Services"

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
sdk/cognitiveservices/azure-ai-transcription/tests.yml	Fixed pipeline configuration structure by changing top-level key from stages: to extends:, following the standard pattern used across the repository
sdk/cognitiveservices/azure-ai-transcription/_metadata.json	Added service_name field with value "Cognitive Services" to the metadata configuration