home: vim: oil: explicitly remove icons

They started appearing on the latest bump, it looks like my
configuration started including `nvim-web-devicons` (see [1]).

I'll probably remove this configuration on the next nixpkgs bump (it's a
good canary to check that I *never* include icons in the future).

[1]: https://github.com/NixOS/nixpkgs/pull/382668

modules/home/vim/plugin/settings/oil.lua

@@ -4,6 +4,8 @@ local wk = require("which-key")
 local detail = false
 
 oil.setup({
+    -- Don't show icons
+    columns = {},
     view_options = {
         -- Show files and directories that start with "." by default
         show_hidden = true,