The tag is present in Lintian version 2.113.26. That is the most recent version we know about.
We use semantic versions.
The patch number is a commit step indicator relative to the
release tag in our Git
You can find the detection logic for this version at commit 43a81d7. For merge requests, please use the latest version in the Lintian check fields/checksums.
This .dsc file contains no Checksum-Sha256 field and hence only weak digests.
This issue will only show up for source packages built with dpkg-source before 1.14.17 (March 2008) and hence will probably never show up when you run Lintian locally but only on https://lintian.debian.org/ for source packages in the archive.
Accordingly it can be fixed by simply rebuilding the source package with a more recent dpkg-source version, i.e. by uploading a new Debian release of the package.