How to pass encryption key inside the replica set pod using MongoDB Enterprise Kubernetes Operator

I have deployed a MongoDB replica set using the MongoDB Enterprise Kubernetes Operator. The Operator is pointing to the Cloud Manager and I can see the resources in the Cloud Manager dashboard.

So far so good!!!

Now I want to enable encryption at rest using Local Key Mangement. I have created a key file using openssl but how to pass this key inside the MongoDB replica set pod? Once the file in passed inside the pod, then I can enable the encryption using the below snippet:

      enableEncryption: true
      encryptionKeyFile: "/foo/my_key"

Since the replica set pod is being triggered by the Kubernetes operator pod, I am struggling to get this work by volume mounts. Can anyone please help me with this?

Thanks in advance!