fix vim.fn.sign_define deprecation and use vim.diagnostic.config.signs instead for neovim

.config/nvim/lua/user/lsp-configs.lua

@@ -156,17 +156,22 @@ lspconfig.yamlls.setup {
     capabilities = capabilities
 }
 
--- change the diagnostic signs to be nerdfonts
-local signs = { Error = " ", Warn = " ", Hint = " ", Info = " " }
-
-for type, icon in pairs(signs) do
-  local hl = "DiagnosticSign" .. type
-  vim.fn.sign_define(hl, { text = icon, texthl = hl, numhl = hl })
-end
-
 vim.diagnostic.config({
   virtual_text = false,
-  signs = true,
+    signs = {
+        text = {
+            [vim.diagnostic.severity.ERROR] = ' ',
+            [vim.diagnostic.severity.WARN] = ' ',
+            [vim.diagnostic.severity.INFO] = ' ',
+            [vim.diagnostic.severity.HINT] = ' ',
+        },
+        linehl = {
+            [vim.diagnostic.severity.ERROR] = 'ErrorMsg',
+        },
+        numhl = {
+            [vim.diagnostic.severity.WARN] = 'WarningMsg',
+        },
+  },
   underline = true,
   update_in_insert = false,
   severity_sort = false,