docker: gateway: bump alpine from 3.22.2 to 3.23.0 in /gateway

Bumps alpine from 3.22.2 to 3.23.0.

---
updated-dependencies:
- dependency-name: alpine
  dependency-version: 3.23.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

gateway/Dockerfile

@@ -56,7 +56,7 @@ WORKDIR $GOPATH/src/github.com/shellhub-io/shellhub/gateway
 ENTRYPOINT ["/entrypoint.sh"]
 
 # production stage
-FROM alpine:3.22.2 AS production
+FROM alpine:3.23.0 AS production
 
 RUN apk add libgcc curl certbot certbot-nginx certbot-dns certbot-dns-digitalocean certbot-dns-cloudflare