adapta-gtk-theme: 3.93.1.14 -> 3.93.1.16

Semi-automatic update generated by https://github.com/ryantm/nixpkgs-update tools.

This update was made based on information from https://repology.org/metapackage/adapta-gtk-theme/versions.

These checks were done:

- built on NixOS

- 0 of 0 passed binary check by having a zero exit code.
- 0 of 0 passed binary check by having the new version present in output.
- directory tree listing: https://gist.github.com/1f7d6359cc7a8a9633e6baffccd4c6e7
- du listing: https://gist.github.com/976b4a761384960b8a30216a39131cee