mate.pluma: 1.21.0 -> 1.21.1 (#42966)

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

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

These checks were done:

- built on NixOS
- /nix/store/qv4p1mlbwak5d9yrpx9asi95nyjqfcss-pluma-1.21.1/bin/pluma passed the binary check.
- /nix/store/qv4p1mlbwak5d9yrpx9asi95nyjqfcss-pluma-1.21.1/bin/.pluma-wrapped passed the binary check.
- 2 of 2 passed binary check by having a zero exit code.
- 0 of 2 passed binary check by having the new version present in output.
- found 1.21.1 with grep in /nix/store/qv4p1mlbwak5d9yrpx9asi95nyjqfcss-pluma-1.21.1
- directory tree listing: https://gist.github.com/f06bd46e4278731e8bf069a5bc4f0f62
- du listing: https://gist.github.com/2e4b1ada7a39f4bb5b224c773d0096c6