Convert Notificationhubs Swagger to Tsp

[mcgallan]

This PR migrates your latest version (identified by the tag in your readme.md) of swagger to TypeSpec. We already tried our best to make sure the TypeSpec represents same as previous swagger. Since we lack the business knowledge, please validate this PR again to make sure it's functional equivalent as before. The local validation step is at Getting started | TypeSpec Azure

Besides, TypeSpec encourages to follow ARM guidelines. Therefore, some representations in your previous swagger will be fixed to follow these guidelines. When you see differences in your local validation, please keep this note in mind.

Please reach out to TypeSpec Discussions Channel if there is any help needed.

[openapi-pipeline-app]

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[openapi-pipeline-app]

PR validation pipeline restarted successfully. If there is ApiView generated, it will be updated in this comment.

[github-actions]

API Change Check

APIView identified API level changes in this PR and created the following API reviews

Language	API Review for Package
Swagger	Microsoft.NotificationHubs
TypeSpec	Microsoft.NotificationHubs

[weidongxu-microsoft]

Should we rename the interface to Namespaces instead?

[pshao25]

I don't think I'll change anything until we have a mature design and mitigation plan on the deprecating operation id.

[JiaqiZhang-Dev]

Same as Weidong, all the interface names now have a suffix "Resources." This change introduces many breaking changes: https://github.com/azure-sdk/azure-sdk-for-go/pull/14591/files. Should they remain consistent with the previous naming?