Don't use links when running in host network mode

What does this MR do?

Docker services are started without links when the executor is configured to run in host mode.

Why was this MR needed?

Previously services were configured to run with links even in host mode leading to crashes:

Health check error:
ContainerCreate: Error response from daemon: conflicting options: host type networking can't be used with links. This would result in undefined behavior (executor_docker.go:1249:0s)

What are the relevant issue numbers?

This might be related to #1307 (closed)