Consider reducing the Action set for the Service Principal

[AndyCW]

@cauldnz : It’d be good to reduce the Action set for the Service Principal if we have time; a. Suggest that removing the Contributor role and instead creating a custom role as part of the setup script would be ideal but I am not sure how rich the set of definable Actions are for the LUIS resource provider. https://docs.microsoft.com/en-us/azure/role-based-access-control/custom-roles https://docs.microsoft.com/en-us/azure/role-based-access-control/resource-provider-operations (I do not see LUIS listed here so may be something to ask PG about)