docker-compose(deps): Bump nginx in /docker/compose

Bumps nginx from 1.31.1-alpine to 1.31.2-alpine.

---
updated-dependencies:
- dependency-name: nginx
  dependency-version: 1.31.2-alpine
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

docker/compose/docker-compose.ci-test.yml

@@ -35,7 +35,7 @@ services:
       - "3143:3143" # IMAP
     restart: unless-stopped
   nginx:
-    image: docker.io/nginx:1.31.1-alpine
+    image: docker.io/nginx:1.31.2-alpine
     hostname: nginx
     container_name: nginx
     ports: