Update dependency prometheus_postgres_exporter to v0.20.0-0

requirements.yml

@@ -72,7 +72,7 @@
   version: v1.10.2-1
   name: prometheus_node_exporter
 - src: git+https://github.com/mother-of-all-self-hosting/ansible-role-prometheus-postgres-exporter.git
-  version: v0.19.1-4
+  version: v0.20.0-0
   name: prometheus_postgres_exporter
 - src: git+https://github.com/mother-of-all-self-hosting/ansible-role-sable.git
   version: v1.18.3-0