Add Postgresus templates to automate postgres backups (#490)

* add postgresus templates to automate backups

* Simplify docker-compose.yml for postgresus service

Removed unnecessary container name and network configuration.

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Co-authored-by: Mauricio Siu <47042324+Siumauricio@users.noreply.github.com>

meta.json

@@ -4541,6 +4541,23 @@
       "webmail"
     ]
   },
+  {
+    "id": "postgresus",
+    "name": "Postgresus",
+    "version": "latest",
+    "description": "Free, open source and self-hosted solution for automated PostgreSQL backups. With multiple storage options and notifications",
+    "logo": "postgresus.svg",
+    "links": {
+      "github": "hhttps://github.com/RostislavDugin/postgresus",
+      "website": "https://postgresus.com",
+      "docs": "https://postgresus.com"
+    },
+    "tags": [
+      "postgres",
+      "backup",
+      "s3"
+    ]
+  },
   {
     "id": "postiz",
     "name": "Postiz",