Recent commit 59356f11c1 ("perlPackages: Ensure all packages have a
license", 2022-08-22) added a license field to Perl packages where the
license was missing. The above mentioned packages got assigned
`unfreeRedistributable` license, which is not precise and makes all
packages depending on them unbuildable without `NIXPKGS_ALLOW_UNFREE`.
The packages actually have a license which SPDX calls
BSD-4-Clause-Shortened (https://spdx.org/licenses/BSD-4-Clause-Shortened.html).
In this commit, we add this license to the list of allowed licenses
and change the license field of the mentioned packages.
Closes#188103
c1b2e4a9b1