Fix deprecated highlight config for gitsigns (#2078)

lua/plugins/configs/others.lua

@@ -51,12 +51,12 @@ end
 
 M.gitsigns = {
   signs = {
-    add = { hl = "DiffAdd", text = "│", numhl = "GitSignsAddNr" },
-    change = { hl = "DiffChange", text = "│", numhl = "GitSignsChangeNr" },
-    delete = { hl = "DiffDelete", text = "󰍵", numhl = "GitSignsDeleteNr" },
-    topdelete = { hl = "DiffDelete", text = "‾", numhl = "GitSignsDeleteNr" },
-    changedelete = { hl = "DiffChangeDelete", text = "~", numhl = "GitSignsChangeNr" },
-    untracked = { hl = "GitSignsAdd", text = "│", numhl = "GitSignsAddNr", linehl = "GitSignsAddLn" },
+    add          = { text = '│' },
+    change       = { text = '│' },
+    delete       = { text = '󰍵' },
+    topdelete    = { text = '‾' },
+    changedelete = { text = '~' },
+    untracked    = { text = '│' },
   },
   on_attach = function(bufnr)
     utils.load_mappings("gitsigns", { buffer = bufnr })