[Artery] Materializer settings are hardcoded into reference HOCON

[Arkatufus]

TODO: Implement HOCON feature to allow the HOCON parser to pull substitution values from another HOCON file and/or Config.

Artery advanced settings (akka.remote.artery.advanced.materializer) uses the ActorMaterializer settings from akka.stream.materializer via substitution, but our HOCON implementation does not have a substitution feature that can substitute a value from an external HOCON/Config.

The settings object is currently being hardcoded (copied from akka.stream.materializer) into the reference HOCON config.