Kubernetes drone-controller: add custom CA to pod

How to add custom CA to drone-controller pod? As I understand, kubernetes pod configuration is creating on-the-fly and I can not add volumes to this pod? I got this error and I don’t know how to avoid it

2019/06/02 10:21:32 [ERR] POST https://drone.xxx.local/rpc/v1/details request failed: Post https://drone.xxx.local/rpc/v1/details: x509: certificate signed by unknown authority
2019/06/02 10:21:32 [DEBUG] POST https://drone.xxx.local/rpc/v1/details: retrying in 10s (25 left)

Is there a way to add kubernetes volume to drone-controller pod?