Fix blank screen on IOU confirm page

[roryabraham]

Details

The option.participantsList may be undefined (per it's prop types here). So this PR ensures that we're safely checking the length of that array.

Fixed Issues

Fixes #2969

Tests / QA Steps

1. Open a chat on an account in the IOU beta.
2. Press the + icon
3. Press "Request Money"
4. Enter an amount in the modal.
5. Hit Next
6. Verify that the app doesn't crash or fail with a white screen.

Tested On

• Web
• Mobile Web
• Desktop
• iOS
• Android

Screenshots

Web

Mobile Web

Desktop

iOS

Android

[roryabraham]

Unfortunately I've got to run and didn't have time to finish testing this on all platforms. Will resume in the AM

[roryabraham]

@stitesExpensify This passed testing on all platforms and is ready for your review :)

[isagoico]

Android - Chat - Nothing happened after clicked Request Money button

Expected Result

The screen should redirect to LHN after clicked Request Money button the

Actual Result

Nothing happened after clicked Request Money button

Action Performed

1. Lunch the app
2. Log in with applause account
3. Press the + icon
4. Press "Request Money"
5. Enter an amount in the modal.
6. Hit Next
7. Select any user
8. Click Request Money button

Platform

Android ✔️

Notes/Images/Video
No workaround found. Only happening on Android app.

Bug5074926_Screen_Recording_20210518-170423_Expensifycash__1_.mp4

[roryabraham]

@isagoico This goes a step further than the QA steps for this PR. Could you please create a separate issue?

[isagoico]

Sure! Issue here #2995