I currently have a setup where I run workflow with an Apache+PHP container as the main container and a Selenium node as a service. The connection to the Selenium node is no problem as per this documentation: https://docs.github.com/en/actions/using-containerized-services/about-service-containers#running-jobs-in-a-container
However since the Selenium node needs to access the Apache node, there is no way I have found connect back to the main container using hostname or localhost/127.0.0.1 (since its not host network). How would one figure out what the containers host is?
I've tried to setup a host network configuration, but it's not allowed in Github Actions Enterprise with self hosted runners, for the customer I work with.