Fix VMSS property type in API response

[yanzhudd]

There's an Azure CLI issue caused by the inconsistence between the Swagger definition and API response.
The actual response could be object type or string, so the definition should be "any" type instead of "object".

[openapi-pipeline-app]

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[openapi-pipeline-app]

Generated ApiView

Language	Package Name	ApiView Link
Go	sdk/resourcemanager/compute/armcompute	Create ApiView timeout. Package is too large and we cannot create ApiView for it.
Java	azure-resourcemanager-compute-generated	https://apiview.dev/Assemblies/Review/eb099b2efb0f4373a854e09003a6b31d?revisionId=c73b5648cf69444c8430654deeea41ba
.Net	Azure.ResourceManager.Compute	There is no API change compared with the previous version
JavaScript	@azure/arm-compute	There is no API change compared with the previous version

[azure-sdk]

API change check

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

Microsoft.Compute