[8.16](backport #4581) [Synthetics]: fix MFA totp method for browser …

…monitors (#4597)

* [Synthetics]: fix MFA totp method for browser monitors (#4581)

(cherry picked from commit 083cf27)

# Conflicts:
#	docs/en/serverless/synthetics/synthetics-mfa.asciidoc

* Delete docs/en/serverless directory

---------

Co-authored-by: Vignesh Shanmugam <[email protected]>
Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

docs/en/observability/synthetics-mfa.asciidoc

@@ -41,7 +41,7 @@ import { journey, step, mfa} from '@elastic/synthetics';
 journey('MFA Test', ({ page, params }) => {
   step('Login using TOTP token', async () => {
     // login using username and pass and go to 2FA in next page
-    const token = mfa.token(params.MFA_GH_SECRET);
+    const token = mfa.totp(params.MFA_SECRET);
     await page.getByPlaceholder("token-input").fill(token)
   });
 });
@@ -51,12 +51,12 @@ For monitors created in the Synthetics UI using the Script editor, the `mfa` obj
 
 ```ts
 step('Login using 2FA', async () => {
-  const token = mfa.token(params.MFA_GH_SECRET);
+  const token = mfa.totp(params.MFA_SECRET);
   await page.getByPlaceholder("token-input").fill(token)
 });
 ```
 
 [NOTE]
 ====
-`params.MFA_GH_SECRET` would be the encoded secret that was used for registering the Synthetics Authentication in your web application.
+`params.MFA_SECRET` would be the encoded secret that was used for registering the Synthetics Authentication in your web application.
 ====