fix: Add group to autocmd (to be able to clear it)

Also added some nice border style to the diagnostics pop-up.

nvim/lsp_client_settings.vim

@@ -46,7 +46,12 @@ lua << EOF
 local nvim_lsp = require("lspconfig")
 
 local on_attach = function(client, bufnr)
+  vim.diagnostic.config({
+    float = { border = "rounded" }
+  })
+
   vim.api.nvim_create_autocmd("CursorHoldI", {
+    group = vim.api.nvim_create_augroup("Diagnostics", { clear = true }),
     buffer = bufnr,
     callback = function()
       vim.diagnostic.open_float({ focusable = false, header = "" })