Support extraVolumeMounts for pod

[Komey]

Linked issue https://github.com/orgs/portainer/discussions/9931#discussioncomment-10556329

This uses extraVolumeMounts to mount host CA to the container for trust internal root CA

# -- List of extra mounts to add (normally used with extraVolumes)
extraVolumeMounts:
- mountPath: /etc/ssl/certs/ca-certificates.crt
  name: host-ca-certificates
  readOnly: true

# -- List of extra volumes to add
extraVolumes:
- hostPath:
    path: /etc/ssl/certs/ca-certificates.crt
  name: host-ca-certificates

[GunnarGrop1]

Bump. I've had to fork this Helm chart to achieve this, since it's indeed very important to be able to trust a self signed CA, for example. For my own purposes I need this for Portainer to be able to trust my SSO platform.