Golang html/template: errors returned from MarshalJSON are not correctly escaped [1.22 backport]

@rolandshoemaker requested issue #65697 to be considered for backport to the next 1.22 minor release.

@gopherbot please open backport issues, this is a PUBLIC track security issue.

Comment From: gopherbot

Change https://go.dev/cl/567535 mentions this issue: [release-branch.go1.22] html/template: escape additional tokens in MarshalJSON errors

Comment From: gopherbot

Closed by merging 056b0edcb8c152152021eebf4cf42adbfbe77992 to release-branch.go1.22.