Update postgres:18.1-alpine Docker digest from 18.1 to 18.1-alpine (docker-compose.yml)

Author: renovate[bot]

docker-compose.yml

@@ -120,7 +120,7 @@ services:
           source: ./docker/extra_settings
           target: /app/docker/extra_settings
   postgres:
-    image: postgres:18.1-alpine@sha256:4eb15de8e7b692c02427a2df278d18eb89422a534e428efb6d43c968250334d4
+    image: postgres:18.1-alpine@sha256:aa6eb304ddb6dd26df23d05db4e5cb05af8951cda3e0dc57731b771e0ef4ab29
     environment:
       POSTGRES_DB: ${DD_DATABASE_NAME:-defectdojo}
       POSTGRES_USER: ${DD_DATABASE_USER:-defectdojo}