Your package build-depends on libgfortran3. That's wrong, you should just
let gfortran pull the right libgfortran (currently libgfortran4).
However your package doesn't seem to use gfortran at all, so please remove
both libgfortran3 and gfortran from build-depends (unless I'm missing
Severity serious as libgfortran3 is part of gcc-6 which we plan to remove.
-- System Information:
Debian Release: buster/sid
APT prefers unstable
APT policy: (800, 'unstable'), (700, 'experimental'), (650, 'testing'), (500,
'unstable-debug'), (500, 'testing-debug')
Architecture: amd64 (x86_64)
Foreign Architectures: i386, armhf
Kernel: Linux 4.14.0-3-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_GB.utf8, LC_CTYPE=en_GB.utf8 (charmap=UTF-8),
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled
Versions of packages libpam-script depends on:
ii libc6 2.26-6
ii libpam0g 1.1.8-3.6
libpam-script recommends no packages.
libpam-script suggests no packages.