metabase: 0.29.2 -> 0.29.3

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

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

These checks were done:

- built on NixOS
- Warning: no invocation of /nix/store/b7bpmc5h45cq2afcmrrsw2w60im3420w-metabase-0.29.3/bin/metabase had a zero exit code or showed the expected version
- 0 of 1 passed binary check by having a zero exit code.
- 0 of 1 passed binary check by having the new version present in output.
- directory tree listing: https://gist.github.com/986f43a4bd9effc51da98989246f0267
- du listing: https://gist.github.com/cec3ac2b5a9a0226fbb8653fbe98ce5e