supercollider: 3.9.2 -> 3.9.3

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

This update was made based on information from https://repology.org/metapackage/supercollider/versions.

These checks were done:

- built on NixOS
- ran ‘/nix/store/4azhvz3aw8jkcs3vib2aaii15yq5rr8k-supercollider-3.9.3/bin/supernova -h’ got 0 exit code
- ran ‘/nix/store/4azhvz3aw8jkcs3vib2aaii15yq5rr8k-supercollider-3.9.3/bin/supernova --help’ got 0 exit code
- ran ‘/nix/store/4azhvz3aw8jkcs3vib2aaii15yq5rr8k-supercollider-3.9.3/bin/sclang -h’ got 0 exit code
- found 3.9.3 with grep in /nix/store/4azhvz3aw8jkcs3vib2aaii15yq5rr8k-supercollider-3.9.3
- directory tree listing: https://gist.github.com/1dcdb0888d56e74baf1a827e371acad1