databases/postgresql??-*: Update to latest versions

Update to 18.6, 17.11, 16.15, 15.19 and 14.24.

This release fixes 28 security vulnerabilities and over 110 bugs
reported over the last several months.

Welcome postgresql19 to the ports tree with 19-beta3.

Note: PostgreSQL 18.5 was skipped due to a regression; the fix
version is 18.6.

PostgreSQL 14 will stop receiving fixes on 2026-11-12.

Changes: https://www.postgresql.org/about/news/postgresql-186-1711-1615-1519-1424-and-19-beta-3-released-3365/
Security: 05d311bc-9991-11f1-bc50-6cc21735f730
(cherry picked from commit 60c44ec8a907bb79b51fc6efb48ea2b7ed4c5d1e)