Fix bug where New Tab Page ad viewed events fail on iOS

[tmancey]

Description:

NTP-SI ad events are failing

Steps to Reproduce

1. Join Rewards
2. View an NTP-SI ad

Actual result:

NTP-SI ad viewed event fails because a served event is not triggered

Expected result:

NTP-SI ad viewed should succeed

Reproduces how often: [Easily reproduced, Intermittent Issue]

Easily reproduced

Brave Version:

• Can you reproduce this issue with the most recent build from TestFlight? Yes
• Can you reproduce this issue with the previous version of the current build from TestFlight? Yes
• Can you reproduce this issue with the current build from AppStore? Yes

Device details:

Website problems only:

• did you check with Brave Shields down?
• did you check in Safari/Firefox (WkWebView-based browsers)?

Additional Information

Temporary fix until 1.53.x which changes how these events are triggered

[kjozwiak]

Verification PASSED on iPhone 11 running iOS 16.5 & iPad Air (3rd Gen) running iPadOS 16.5 using the following build(s):

1.51.2 (23.6.5.21)

We needed to verify the above via a call with @tackley @tmancey & @vlad-hoff as we couldn't verify the above on Dev builds due to the following:

• Dev builds are not displaying any NTP SI but have the ability to enable deeper logging for rewards/ads
• Production builds are displaying NTP SI but don't have the ability to enable deeper logging for rewards/ads

Because the above started happening on 1.49 (C111), we were able to monitor the back-end and confirmed that viewed, clicked and landed were working from a device from Canada running C113. Because this was broken via C111, there was no traffic coming from C113 builds so it was easy to verify it was my requests.