[BUG] Giving Quota Error for existing resource on redeploying in incremental mode.

Describe the bug
In my subscription, Azure Digital Twins Count Limit is 10 and I have exhausted the limit. But when I deploy the bicep in incremental mode with same name as of one of the existing ADT instances, it gives me quota error.

I have encountered this issue multiple times in past for other resources as well.

Steps To Reproduce
resource digitalTwinsInstance 'Microsoft.DigitalTwins/digitalTwinsInstances@2023-01-31' = {
name: ''
location: ''
}

az deployment group what-if -g --template-file .\adt.bicep

Error:
InvalidTemplateDeployment - The template deployment 'adt' is not valid according to the validation procedure. The tracking id is ''. See inner errors for details.
LimitExceeded - Target - ''. Subscription '' has '10' instances in this region. Please visit https://aka.ms/dtV2limits for details.

Expected behavior
It should detect that same resource is being deployed in incremental mode.

Environment
Az-Cli 2.49.0

Start with the Azure Digital Twins resource in adt.bicep and reproduce the case using az deployment group what-if in incremental mode against a subscription at its regional limit. Investigate why an existing instance is treated as a new resource; done means redeploying the same resource name no longer produces the quota error.