nvim: statusline: Fix git status being nil

signs.add/change/delete can be nil for a file not yet being tracked
with git. This was broken in 703d23c.

arch-packages/pkglist.txt

@@ -374,7 +374,6 @@ unzip
 upower
 usb_modeswitch
 usbutils
-uv
 v4l2loopback-dkms
 valgrind
 vimiv-qt

nvim/.config/nvim/after/plugin/mini.lua

@@ -1,6 +1,8 @@
 local remap = vim.keymap.set
 local opts  = { noremap=true, silent=true, unique=true }
 
+-- Comment lines
+require('mini.comment').setup()
 -- Diff hunks
 require('mini.diff').setup({
   view = {