chore(which-key): remove unnecessary icons (#5461)

## Description

These are already handled by which-key exactly the same way, no need to
re-declare them here. Removing them from here has no effect.

## Related Issue(s)

N/A

## Screenshots

![Screenshot 2025-01-23 at 21 21
14](https://github.com/user-attachments/assets/d9f777e8-d514-4836-9314-03a66cc5a34b)

## Checklist

- [x] I've read the
[CONTRIBUTING](https://github.com/LazyVim/LazyVim/blob/main/CONTRIBUTING.md)
guidelines.

lua/lazyvim/plugins/editor.lua

@@ -74,8 +74,8 @@ return {
           { "<leader>gh", group = "hunks" },
           { "<leader>q", group = "quit/session" },
           { "<leader>s", group = "search" },
-          { "<leader>u", group = "ui", icon = { icon = "󰙵 ", color = "cyan" } },
+          { "<leader>u", group = "ui" },
-          { "<leader>x", group = "diagnostics/quickfix", icon = { icon = "󱖫 ", color = "green" } },
+          { "<leader>x", group = "diagnostics/quickfix" },
           { "[", group = "prev" },
           { "]", group = "next" },
           { "g", group = "goto" },