Bump chainguard/nginx from 391d723 to b70db73

Bumps [chainguard/nginx](https://github.com/chainguard-images/images) from `391d723` to `b70db73`.
- [Commits](https://github.com/chainguard-images/images/commits)

---
updated-dependencies:
- dependency-name: chainguard/nginx
  dependency-type: direct:production
...

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

prod.Dockerfile

@@ -15,7 +15,7 @@ COPY /frontend/. .
 # build app for production with minification
 RUN npm run build
 
-FROM cgr.dev/chainguard/nginx:latest@sha256:391d7234a6648dabd2fafa3cfa2326a026e6e85e029a7963199990d4bc437819
+FROM cgr.dev/chainguard/nginx:latest@sha256:b70db730fc8d02df4fcc3ed9fea2718a40225e8054f7e854fbd636dc5563cdcf
 EXPOSE 8081
 COPY --from=builder /frontend/dist /var/lib/nginx/html
 COPY nginx.conf /etc/nginx/conf.d/ris-adm-vwv.conf