In an upcoming patch, we'll enable enforcement that all FLUTTER_NOLINT
comments include an issue link. This migrates the remaining uses to that
format.
Bug: https://github.com/flutter/flutter/issues/68273
This was only necessary when the Engine had to build in multiple buildroots
where the sources where checked out at different paths relative to the
buildroot. This is no longer the case and there are already cases GN rules
have been written that mix and match variable usage with the direct
specification of the path to the Flutter sources relative to the sole buildroot.
