cmd/go: potential code smuggling using doc comments (CVE-2025-61732) [1.25 backport]

[gopherbot]

@neild requested issue #76697 to be considered for backport to the next 1.25 minor release.

@gopherbot please open backport issues for this security fix.

[taufanharyudiansah6-byte]

#77129 (comment)