pulse-server: module-null-sink: do not use client's core

Do not use the client's connection to create the adapter object,
instead, create a new connection. This avoids the need for setting
object.linger=true, which guarantees that when the pulse server goes
down, the null sink is cleaned up.
41 jobs for pw_pulse_null_sink_create_core in 4 minutes and 43 seconds (queued for 23 seconds)