Key vault access from Azure load test using RBAC role

Hi, I'm trying to retrieve secret from Azure Key Vault during the execution of a JMeter test using an Azure Load Test. I've configured secret parameter in the load test and am attempting to access it in the JMeter script using ${__GetSecret(<my-secret-name>)}. The managed identity for Azure Load Testing has been assigned the 'Key Vault Secrets User' RBAC role to grant access on Key Vault. However, the test fails with the error shown below.

ERROR c.a.c.j.j.f.GetSecret: __GetSecret function is not allowed in a sampler or a listener

We are not using Key Vault access policies as described in the Microsoft documentation, and we need this to work using RBAC.

https://learn.microsoft.com/en-us/azure/load-testing/how-to-parameterize-load-tests?tabs=jmeter#use-secrets-in-apache-jmeter