Microsoft.Kusto/clusters/databases/principalAssignments@2021-01-01 resource names

**Bicep version**
Bicep CLI version 0.4.613

**Describe the bug**
Microsoft.Kusto/clusters/databases/ can contains trademarked or reserved word while Microsoft.Kusto/clusters/databases/principalAssignments can not - so in case database include trademarked or reserved word this resource creation is not going to work and it will fail with :
ReservedResourceName - The resource name 'resourceName' or a part of the name is a trademarked or reserved word.

**To Reproduce**
1. create kusto cluster
2. create database under the same cluster and include one of the trademarked or reserved word (https://docs.microsoft.com/en-us/azure/azure-resource-manager/templates/error-reserved-resource-name)
3. try co create Microsoft.Kusto/clusters/databases/principalAssignments

Start by reproducing the deployment with a Kusto cluster, a database whose name contains a reserved or trademarked word, and a principalAssignments resource. Compare the behavior with the Azure reserved-resource-name guidance; done means the principalAssignments resource can be created for such a database without the reported ReservedResourceName failure.

Written by the indexing model from the issue text.