Fix gruvbox diff colors

See:
https://github.com/ellisonleao/gruvbox.nvim/issues/105#issuecomment-1480547367

lua/install-plugins.lua

@@ -226,12 +226,6 @@ return require('packer').startup(function(use)
   }
   use 'nvim-telescope/telescope-ui-select.nvim'
   use 'nvim-telescope/telescope-project.nvim'
-  use {
-    'ellisonleao/gruvbox.nvim',
-    config = function()
-      require('plugins.gruvbox')
-    end,
-  }
   use 'NLKNguyen/papercolor-theme'
   use {
     'akinsho/toggleterm.nvim',
@@ -447,7 +441,15 @@ return require('packer').startup(function(use)
       require('plugins.which-key-nvim')
     end
   }
+  use {
+    'ellisonleao/gruvbox.nvim',
+    config = function()
+      require('plugins.gruvbox')
+    end,
+  }
   use 'eandrju/cellular-automaton.nvim'
+  use 'nyoom-engineering/oxocarbon.nvim'
+  use 'folke/tokyonight.nvim'
 
   -- Automatically set up your configuration after cloning packer.nvim
   -- Put this at the end after all plugins

lua/plugins/gruvbox.lua

@@ -1,5 +1,3 @@
-local colors = require("gruvbox.palette").colors;
-
 require("gruvbox").setup({
   undercurl = true,
   underline = true,
@@ -36,11 +34,3 @@ require("gruvbox").setup({
   }
 })
 vim.o.background = "dark"
-
--- TODO: how to apply this when colorscheme changes?
-vim.api.nvim_set_hl(0, 'DiffDelete', { bg = "none", fg = colors.dark2 })
-vim.api.nvim_set_hl(0, 'DiffviewDiffDelete', { bg = "none", fg = colors.dark2 })
-vim.api.nvim_set_hl(0, 'DiffviewDiffAddAsDelete', { bg = "#370000" })
-vim.api.nvim_set_hl(0, 'DiffAdd', { bg = "#393400" }) -- #122f2f
-vim.api.nvim_set_hl(0, 'DiffChange', { bg = "#222a36" })
-vim.api.nvim_set_hl(0, 'DiffText', { bg = "#2f3f5c" }) -- #2f3f5c