The tag is present in Lintian version 2.104.234. That is the most recent version we know about.
The installation package ships a GFORTRAN module which does not declare a module version number. That number is needed to establish the proper prerequisites for binary rebuilds.
Refer to Bug#796352, Bug#714730, and https://salsa.debian.org/science-team/dh-fortran-mod/blob/debian/master/dh_fortran_mod.in for details.