devel/ruby-build: Update to 20250716
This is a leaf port, and because to the nature of the tool, it is
worthwhile to always keep it up to date.
Changes: https://github.com/rbenv/ruby-build/releases/tag/v20250716
(cherry picked from commit 476e2c0e4f33b5d5b4ebefc3d4ed1f95df75e8b1)