fix

init.lua

@@ -340,6 +340,7 @@ vim.lsp.handlers['textDocument/publishDiagnostics'] = vim.lsp.with(
 vim.lsp.diagnostic.on_publish_diagnostics, { virtual_text = false })
 require('mason').setup()
 require("mason-null-ls").setup({
+    ensure_installed = { 'prettierd', 'rubocop' },
     handlers = {},
 })
 require('mason-lspconfig').setup()