nvim: init: Use a size of 2 for sign column

This helps to display both diagnostic signs and git gutter at the same
time. Use automatic resize keeping minimum at 1 and maximum at 2.

nvim/.config/nvim/init.lua

@@ -45,7 +45,7 @@ vim.o.diffopt        = 'filler,internal,algorithm:histogram,indent-heuristic'
 vim.o.scrolloff      = 999
 vim.o.formatoptions  = "crqn1j"
 vim.o.relativenumber = true
-vim.o.signcolumn     = "yes"
+vim.o.signcolumn     = "auto:1-2"
 vim.o.cursorline     = true
 vim.o.cursorlineopt  = "number"