fix(help): clear git signs before draw

lua/nvim-tree/renderer/init.lua

@@ -24,6 +24,7 @@ local function _draw(bufnr, lines, hl, signs)
   api.nvim_buf_set_lines(bufnr, 0, -1, false, lines)
   M.render_hl(bufnr, hl)
   api.nvim_buf_set_option(bufnr, "modifiable", false)
+  vim.fn.sign_unplace(git.SIGN_GROUP)
   for _, sign in pairs(signs) do
     vim.fn.sign_place(0, git.SIGN_GROUP, sign.sign, bufnr, { lnum = sign.lnum, priority = 1 })
   end