[3.13] GH-118447: Fix FreeBSD test failures. (GH-119170) (#119181)

GH-118447: Fix FreeBSD test failures. (GH-119170)

Apparently only macOS requires read permission to call `readlink()` on a
symlink.
(cherry picked from commit 4b7667172898d440c1931ae923446c6a5ef1765e)

Co-authored-by: Barney Gale <barney.gale@gmail.com>