Feat: Add Color Configuration (#82)

This MR adds the ability to customize colors for the discussion tree

lua/gitlab/utils/init.lua

@@ -1,6 +1,12 @@
 local Job = require("plenary.job")
 local M = {}
 
+M.get_colors_for_group = function(group)
+  local normal_fg = vim.fn.synIDattr(vim.fn.hlID(group), "fg")
+  local normal_bg = vim.fn.synIDattr(vim.fn.hlID(group), "bg")
+  return { fg = normal_fg, bg = normal_bg }
+end
+
 M.get_current_line_number = function()
   return vim.api.nvim_call_function("line", { "." })
 end