migrate rustc_query_system to use SessionDiagnostic issues: * variable list is not supported in fluent * ~~cannot have two sub diagnostic with the same tag (eg. 2 .note or 2 .help)~~ allow multiple tag with SessionSubdiagnostic derive
migrate rustc_query_system to use SessionDiagnostic issues: * variable list is not supported in fluent * ~~cannot have two sub diagnostic with the same tag (eg. 2 .note or 2 .help)~~ allow multiple tag with SessionSubdiagnostic derive