Not able to create AKS cluster with https proxy config using terraform provider v3.3.0

We are trying to create the private AKS cluster with http proxy config settings

A http_proxy_config block supports the following:

http_proxy - (Optional) The proxy address to be used when communicating over HTTP.

https_proxy - (Optional) The proxy address to be used when communicating over HTTPS.

no_proxy - (Optional) The list of domains that will not use the proxy for communication.

Our code looks like this:
http_proxy_config {
http_proxy = lookup(each.value, “http_proxy”, null)
https_proxy = lookup(each.value, “https_proxy”, null)
no_proxy = lookup(each.value, “no_proxy”, null)
trusted_ca = lookup(each.value, “trusted_ca”, null)
and we are passing null value to trusted_ca as it is an optional field but our cluster is getting failted due to below error:
Error: [0m[0m[1mcreating Cluster: (Managed Cluster Name “aks-cus-tools-dev-001” / Resource Group “rg-cus-mgmt-nonprod-akstools”): containerservice.ManagedClustersClient#CreateOrUpdate: Failure sending request: StatusCode=400 – Original Error: Code=“HTTPProxyTrustedCAPEMDecodeFailure” Message=“failed to decode HTTPProxyConfig.TrustedCA to PEM after base64 decoding.”