Remove outdated note that cachix will get installed

README.md

@@ -6,9 +6,7 @@
 Uses [nix-emacs-ci](https://github.com/purcell/nix-emacs-ci) to provide binaries for a number of different Emacs versions.
 
 Since that project uses Nix, Nix will be installed automatically if
-necessary, along with the "cachix" tool which enables downloads of the
-cached binaries. If you already have nix and possibly cachix
-installed, the existing installations will be used.
+necessary.
 
 Note also that only Linux and MacOS are supported, since Nix is not
 available on Windows.