find_program: Revert "Find programs that are executable but not readable"
The fix in commit 86e6349ef7 (find_program: Find programs that are
executable but not readable, 2020-04-04, v3.18.0-rc1~372^2) can break
existing projects that were (likely accidentally) relying on the
old behavior to find files that are readable but not executable.
Revert the fix for now. We can re-introduce it with a policy later.
Instead of reverting the test case, update it to cover the old behavior.
That can serve as a reference for testing the policy when introduced.
Fixes: #20814
Issue: #10468
3 files changed
