chore: remove unused plugin

nvim/lua/plugins/dashboard.lua

@@ -3,11 +3,7 @@ return {
     "goolord/alpha-nvim",
     event = "VimEnter",
     opts = function()
-      local status_ok, alpha = pcall(require, "alpha")
-      if not status_ok then
-        return
-      end
-
+      local alpha = require("alpha")
       local dashboard = require("alpha.themes.dashboard")
       dashboard.section.header.val = {
         [[ _______       ___           _______. __    __   __   _______ ]],