removed java ftplugin file, as mason-ls now does not need one.

neovim/.config/nvim/lua/LSPconfig.lua

@@ -38,8 +38,8 @@ require("mason-lspconfig").setup_handlers({
 		require('rust-tools-setup')
 		on_attach()
 	end,
-	["sumneko_lua"] = function()
-		require('lspconfig').sumneko_lua.setup {
+	["lua_ls"] = function()
+		require('lspconfig').lua_ls.setup {
 			settings = {
 				Lua = {
 					diagnostics = {

neovim/.config/nvim/lua/packages.lua

@@ -44,8 +44,8 @@ return require('packer').startup(function(use)
 			config = function()
 				require("mason-lspconfig").setup({
 					ensure_installed = {
-						"sumneko_lua",
-						"rust_analyzer",
+						'lua_ls',
+						'rust_analyzer',
 						'pyright',
 						'bashls',
 						'texlab',