js-api: Migrate and test create-user example.

templates/zerver/api/create-user.md

@@ -14,25 +14,8 @@
 {tab|js}
 
 More examples and documentation can be found [here](https://github.com/zulip/zulip-js).
-```js
-const zulip = require('zulip-js');
 
-// The user for this zuliprc file must be an organization administrator.
-const config = {
-    zuliprc: 'zuliprc-admin',
-};
-
-zulip(config).then((client) => {
-    // Create a user
-    const params = {
-        email: 'newbie@zulip.com',
-        password: 'temp',
-        full_name: 'New User',
-        short_name: 'newbie'
-    };
-    client.users.create(params).then(console.log);
-});
-```
+{generate_code_example(javascript)|/users:post|example(admin_config=True)}
 
 {tab|curl}
 

zerver/openapi/javascript_examples.js

@@ -58,8 +58,21 @@ const ExamplesHandler = function () {
     };
 };
 
-const {main} = ExamplesHandler();
+const {main, add_example} = ExamplesHandler();
 
 // Declare all the examples below.
 
+add_example('create_user', '/users:post', 200, async (client) => {
+    // {code_example|start}
+    const params = {
+        email: 'newbie@zulip.com',
+        password: 'temp',
+        full_name: 'New User',
+        short_name: 'newbie',
+    };
+
+    return await client.users.create(params);
+    // {code_example|end}
+});
+
 main();