replace intellitab with auto-indent

after/plugin/auto-indent.lua

@@ -0,0 +1,10 @@
+local status_ok, indent = pcall(require, "auto-indent")
+if not status_ok then
+	return
+end
+
+indent.setup {
+  indentexpr = function(lnum)
+    return require("nvim-treesitter.indent").get_indent(lnum)
+  end
+}