Add Teams custom cmdlets for Pre-Approval

[subray2014]

Fixes #

Changes proposed in this pull request

Identity has recently exposed APIs to create pre-approval permission grant policies which allow admins to configure whether specific apps can be granted a set of permissions based on sensitivity of the involved data. Since these policies operate on an AAD app level, the Teams workload wants to build a TeamsApp-centric abstraction on top of these policies in collaboration with Identity. Teams is planning to launch a set of cmdlets which provide a simple experience to admins to pre-approve RSC permissions specific to Teams.
The current set of APIs developed by Identity operate on a set of identifiers different from the Teams ecosystem. The preapproval policy APIs work on AAD apps. In the Teams Admin Portal, admins operate on Teams Apps. They approve/block or setup policies on Teams Apps. It is expected that the RSC preapproval operation will be applied in a recursive manner on all components associated with a Teams App such as the AAD app backing it. We need a way to bridge this gap and provide admins with a way of approving RSC for Teams Apps.

This change adds a set of custom cmdlets to the Teams workload:

1. New-MgBetaTeamsAppPreapproval - Perform the set of steps needed to create a preapproval policy and associate the AAD app backing a Teams App with it.
   Params:
   a. TeamsAppId - Id of the app being approved.
   b. ResourceSpecificApplicationPermissionsAllowedForTeams - Permissions allowed to the Teams App when installed in teams once this instance has been created.
   c. ResourceSpecificApplicationPermissionsAllowedForChats - Permissions allowed to the Teams App when installed in chats once this instance has been created.
   d. TeamLevelSensitivityLabelCondition - Condition for whether sensitivity labels must be applied on teams for this approval to take effect.
   e. SpecificSensitivityLabelIdsApplicableToTeams - If TeamLevelSensitivityLabelCondition required specific labels, then this param identifies those label Ids.

2. Get-MgBetaTeamsAppPreapproval - Get preapproval policy associated with the AAD app backing a Teams App. This cmdlet will output a custom object which flattens the preapproval policy and provides a user friendly view to the admin.
   Params:
   a. TeamsAppId - Id of the Teams app

3. Update-MgBetaTeamsAppPreapproval - Perform the set of steps needed to update preapproval policy associated with the AAD app backing a Teams App.
   Params:
   a. TeamsAppId - Id of the Teams app.
   b. ResourceSpecificApplicationPermissionsAllowedForTeams - Permissions allowed to the Teams App when installed in teams once this instance has been created.
   c. ResourceSpecificApplicationPermissionsAllowedForChats - Permissions allowed to the Teams App when installed in chats once this instance has been created.
   d. TeamLevelSensitivityLabelCondition - Condition for whether sensitivity labels must be applied on teams for this approval to take effect.
   e. SpecificSensitivityLabelIdsApplicableToTeams - If TeamLevelSensitivityLabelCondition required specific labels, then this param identifies those label Ids.

4. Remove-MgBetaTeamsAppPreapproval - Remove the association between a Teams App and a pre approval policy and delete the policy.
   Params:
   a. TeamsAppId - Id of the Teams app

Other links

[peombwa]

Please singularize Teams in the command names to be consistent with existing commands:

*-MgBetaTeamsAppPreApproval -> *-MgBetaTeamAppPreApproval.