Product subscription should have option to select AAD group in the Access section

**Every bug report should have precise description and reproduction steps; console traces or source code references are appreciated.**
When Product is created in APIM, one subscription is also created with the product. But when you go to product subscription and select a scope and users, there is no option for selecting whole AAD group for the subscription. Please find below image for the same. Only user option is there.

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## Bug description

A clear and concise description of the bug.

## Reproduction steps

1. Go to APIM Instance.
2. Click on Product blade and create one product
3. Go to the created product and select subscription blade.
4. click on subscription which will open above screen in snapshot
5. you can see there is no option to select AAD group for the subscription.

## Expected behavior

Due to this every developer/user has to request for the new subscription and go for a approval flow. If AAD group has been assigned all the AD group user can have the same subscription for them and use it.

## Is your portal managed or self-hosted?

Self-hosted

## Release tag or commit SHA (if using self-hosted version)

commit `f3d70320cad966f601f7cde54a50cd767a017726`

## API Management service name

grd-dev-eus2-gapi-apim-01

## Environment

- Operating system: Any
- Browser: Any
- Version: NA
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## Additional context

Add any other context about the problem here, including screenshots.

Start by reproducing the Product subscription Access flow in the self-hosted portal at commit f3d70320cad966f601f7cde54a50cd767a017726. Done means the subscription can select an AAD group, and users in that group can use the shared subscription without requesting individual access.

Written by the indexing model from the issue text.