docker: bump postgres from 18.3-alpine to 18.4-alpine (#586)

Bumps postgres from 18.3-alpine to 18.4-alpine.

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

docker-compose.dev.yaml

@@ -2,7 +2,7 @@ name: riverui-dev
 
 services:
   postgres:
-    image: "postgres:18.3-alpine@sha256:54451ecb8ab38c24c3ec123f2fd501303a3a1856a5c66e98cecf2460d5e1e9d7"
+    image: "postgres:18.4-alpine@sha256:96d56f7f57c6aacd1fcb908bc83b345ec5f83231ee486dd66a1baadce274db88"
     environment:
       - POSTGRES_USER=postgres
       - POSTGRES_PASSWORD=postgres