Network Policies block plugin marketplace and update checks

Not sure if we want to enable these, but just in case. Need to allow egress...

2021.09.30 17:45:50 ERROR web[AXw3zUXYnfUJFnEEAABT][o.s.s.p.UpdateCenterClient] Fail to connect to update center
org.sonar.api.utils.SonarException: Fail to download: https://update.sonarsource.org/update-center.properties (no proxy)