www/nginx: Update to 1.30.4

Changes:

*) Security: heap buffer overflow when using the map directive with

regex matching (CVE-2026-42533)

*) Security: uninitialized memory access when using unnamed regex

captures with the "slice" directive or background cache update
(CVE-2026-60005)

*) Security: use-after-free when processing a specially crafted

proxied backend response with the ngx_http_ssi_filter_module
(CVE-2026-56434)

Release Notes: https://nginx.org/en/CHANGES-1.30
Security: 56feeac6-8263-11f1-92ba-bc24110523fe
Security: CVE-2026-42533
Security: CVE-2026-56434
Security: CVE-2026-60005

PR: 296830

Sponsored by: Netzkommune GmbH

(cherry picked from commit 96b7b9b5af971bff4b0e1ff0c6313297a3c3839f)