chore(deps): update postgres:latest docker digest to 888402a (#2592)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| postgres | digest | `79c927b` -> `888402a` |

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.devcontainer/docker-compose.yml

@@ -20,7 +20,7 @@ services:
     # (Adding the "ports" property to this file will not forward from a Codespace.)
 
   db:
-    image: postgres:latest@sha256:79c927b43c8bf2fc1e78b7f4badb394237ee0001032324ef015da562e57a5dcd
+    image: postgres:latest@sha256:888402a8cd6075c5dc83a31f58287f13306c318eaad016661ed12e076f3e6341
     restart: unless-stopped
     volumes:
       - postgres-data:/var/lib/postgresql/data