Update locator.clear example

The existing example might have confused readers since an empty input
element was being cleared. The change now brings in an example where
an input field is filled in and then cleared.

docs/sources/next/javascript-api/k6-experimental/browser/locator/clear.md

@@ -23,11 +23,12 @@ Clears text boxes and input fields (`input`, `textarea` or `contenteditable` ele
 {{< code >}}
 
 ```javascript
+import { check } from 'k6';
 import { browser } from 'k6/experimental/browser';
 
 export const options = {
   scenarios: {
-    browser: {
+    ui: {
       executor: 'shared-iterations',
       options: {
         browser: {
@@ -39,11 +40,26 @@ export const options = {
 };
 
 export default async function () {
-  const page = browser.newPage();
+  const context = browser.newContext();
+  const page = context.newPage();
 
-  await page.goto('https://test.k6.io/browser.php');
+  await page.goto('https://test.k6.io/my_messages.php', { waitUntil: 'networkidle' });
 
-  page.locator('#text1').clear();
+  // Fill an input element with some text that we will later clear.
+  page.locator('input[name="login"]').type('admin');
+
+  // This checks that the element has been filled with text.
+  check(page, {
+    not_empty: (p) => p.locator('input[name="login"]').inputValue() != '',
+  });
+
+  // Now clear the text from the element.
+  page.locator('input[name="login"]').clear();
+
+  // This checks that the element is now empty.
+  check(page, {
+    empty: (p) => p.locator('input[name="login"]').inputValue() == '',
+  });
 
   page.close();
 }