net/keycloak: Update 26.7.3 => 26.7.4
Release Notes:
https://www.keycloak.org/2026/09/keycloak-2674-released
PR: 298627
Security: CVE-2026-90997
Security: CVE-2026-79651
Security: CVE-2026-74909
Security: CVE-2026-19607
Security: CVE-2026-17526
Security: CVE-2026-18212
Sponsored by: UNIS Labs (vvd, commit patch)
MFH: 2026Q3
(cherry picked from commit de7579f11868b83a4ee47126823fe6509b2df6fe)