Disable the ACR admin login and use serverless compute for pipelines

[eddmik]

Describe your suggestion

As soon as I disable the admin login I cannot use the serverless compute as I have to attach the managed identity which is impossible for serverless compute. Is my understanding correct or there is still way to do so. When I try to pull the environment in my pipeline I get the following error

Failed to pull Docker image acrnlpplatformdev000.azurecr.io/azureml/azureml_23...... This error may occur because the compute could not authenticate with the Docker registry to pull the image. If using ACR please ensure the ACR has Admin user enabled or a Managed Identity with `AcrPull` access to the ACR is assigned to the compute. If the ACR Admin user's password was changed recently it may be necessary to synchronize the workspace keys.","MessageFormat":null,"MessageParameters":{},"ReferenceCode":null,"DetailsUri":null,"Target":null,"Details":[],"InnerError":null,"DebugInfo":null,"AdditionalInfo":null},"Correlation":null,"Environment":null,"Location":null,"Time":"0001-01-01T00:00:00+00:00","ComponentName":"CommonRuntime"}
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### Additional details

_No response_