notmuch: 0.26.2 -> 0.27

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

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

These checks were done:

- built on NixOS
- /nix/store/fc0y8jb20kfm3v4yy3zzc6ipidc1ks1c-notmuch-0.27/bin/notmuch passed the binary check.
- Warning: no invocation of /nix/store/fc0y8jb20kfm3v4yy3zzc6ipidc1ks1c-notmuch-0.27/bin/notmuch-emacs-mua had a zero exit code or showed the expected version
- 1 of 2 passed binary check by having a zero exit code.
- 1 of 2 passed binary check by having the new version present in output.
- found 0.27 with grep in /nix/store/fc0y8jb20kfm3v4yy3zzc6ipidc1ks1c-notmuch-0.27
- directory tree listing: https://gist.github.com/2a14e6349ea43a555857f9e30bf328ff
- du listing: https://gist.github.com/d08317825ff4ade027455942eb367fdb