Gitlab runner does not use system certs for S3 cache

We currently have our internal CA added to system certs (i.e available in /etc/ssl/certs) and for other gitlab-runner operations like registering it appears to be getting it and working.

But for cache operations I get "tls: failed to verify certificate: x509: certificate signed by unknown authority".

I tried setting tls-ca-file = "/etc/ssl/certs/ca-certificates.crt" in [[runners]] per docs (the file does contain our certs as it is updated with update-ca-certificates, but it appears to not affect the caching.

 [runners.cache]
    Shared = true
    type = "s3"
    path = "cache"
    [runners.cache.s3]
      ServerAddress = "minio1.example.com"
      AccessKey = "gitlab-runner"
      SecretKey = "abcd"
      BucketName = "gitlab-runner"

The runner is talking with gitlab server (which is using same internal CA) just fine, it's just caching that's the problem.

Version: 18.0, installed from packages