www/tt-rss: Update to g20250704 (46e05583a991f2d)

• Update to g20250704 (46e05583a991f2d)
• Remove MYSQL references. See 20250511 [1]
  • mysql support continues to exist in 2025Q3
• Fully depend on pdo_pgsql

[1] https://cgit.freebsd.org/ports/tree/UPDATING

PR: 288069