The listed file or maintainer script appears to reference the build path used to build the package as specified in the Build-Path field of the .buildinfo file.
This is likely to cause the package to be unreproducible, but it may also indicate that the package will not work correctly outside of the maintainer's own system.
Please note that this tag will not appear unless the .buildinfo file contains a Build-Path field. That field is optional. You may have to set DEB_BUILD_OPTIONS=buildinfo=+path or use --buildinfo-option=--always-include-path with dpkg-buildpackage when building.
Refer to https://reproducible-builds.org/, https://wiki.debian.org/ReproducibleBuilds/BuildinfoFiles, and the dpkg-genbuildinfo(1) manual page for details.