Golang os/exec: LookPath bug: incorrect expansion of "", "." and ".." in some PATH configurations [1.23 backport]

@neild requested issue #74466 to be considered for backport to the next 1.23 minor release.

@gopherbot please create backport issues. This is a PUBLIC track security issue.

Comment From: gopherbot

Change https://go.dev/cl/691855 mentions this issue: [release-branch.go1.23] os/exec: fix incorrect expansion of "", "." and ".." in LookPath

Comment From: gopherbot

Closed by merging CL 691855 (commit 8fa31a2d7d9e60c50a3a94080c097b6e65773f4b) to release-branch.go1.23.