Release notes for version 0.39.1

Release date: 24 Mar 2025

• update dashboards and rules
• update common dependency 0.0.39 -> 0.0.42
• set default vmalertmanager image to 0.28.1
• fix additional notifier config rendering. See this issue.
• add default external.alert.source. See this issue.
• add .Values.vmcluster.spec.vmselect.enabled and .Values.vmcluster.spec.vminsert.enabled flags to disable vmselect or vminsert. See this issue.