nvim: update lua ls config

.config/nvim/lua/my/lsp.lua

@@ -149,8 +149,10 @@ if vim.fn.executable('clangd') > 0 then
     })
 end
 
+-- TODO: re-check config recommendation, looks like some things changed
+-- <https://github.com/neovim/nvim-lspconfig/blob/master/doc/server_configurations.md#lua_ls>
 if vim.fn.executable('lua-language-server') > 0 then
-    lspconfig.sumneko_lua.setup({
+    lspconfig.lua_ls.setup({
         settings = {
             Lua = {
                 runtime = {