Update postgres:16.6-alpine Docker digest to a11ddaf (#54)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

plausible/docker-compose.yml

@@ -7,7 +7,7 @@ networks:
 services:
   plausible_db:
     restart: unless-stopped
-    image: postgres:16.6-alpine@sha256:91e75546b4f229fa92cec21a2bf831ba03a1c101fc197daafff657f153e93a39
+    image: postgres:16.6-alpine@sha256:a11ddaf48f067a3d305734b76ffb42e7446a97d1d4a75d1899ff4b128e88e870
     volumes:
       - /home/aosus/plausible/postgres:/var/lib/postgresql/data
     environment: