[backport] fix broken link to non-existing c2nim manual html, fixes #12537 [ci skip] (#12544)
[backport] fix broken link to non-existing c2nim manual html, fixes #12537 [ci skip] (#12544)


dom96/Nim,dom96/Nim,dom96/Nim,dom96/Nim,dom96/Nim,dom96/Nim,dom96/Nim