refactor(docs-infra): remove linenums=false since it is now the default (#31674)

PR Close #31674

aio/tools/transforms/remark-package/services/handlers/code.js

@@ -4,9 +4,7 @@
 module.exports = function code(h, node) {
   var value = node.value ? ('\n' + node.value + '\n') : '';
   var lang = node.lang && node.lang.match(/^[^ \t]+(?=[ \t]|$)/);
-  var props = {
-    linenums: 'false'
-  };
+  var props = {};
 
   if (lang) {
     props.language = lang;