os/exec: environForSysProcAttr is never called as sysattr.Env is never nil [1.14 backport]

[toothrot]

@ianlancetaylor requested issue #35314 to be considered for backport to the next 1.14 minor release.

I have no idea.

@gopherbot Please open backport issues

This may be security related on Windows systems.

[gopherbot]

Change https://golang.org/cl/226281 mentions this issue: [release-branch.go1.14] os/exec: use environment variables for user token when present

[gopherbot]

Closed by merging e6f15fa to release-branch.go1.14.