Fix #7969: [Follow up to #7860] Data on NTP with SI is not aligned properly

[soner-yuksel]

Summary of Changes

Fixing should show NTP callouts on for default browsing on SI

This pull request fixes #7969

Submitter Checklist:

• Unit Tests are updated to cover new or changed functionality
• User-facing strings use NSLocalizableString()
• New or updated UI has been tested across:
  • Light & dark mode
  • Different size classes (iPhone, landscape, iPad)
  • Different dynamic type sizes

Test Plan:

• Fresh install and launch Brave
• Start onboarding flow > Don't set Brave as the default browser and select Not now
• Tap Done > Wait until landed on NTP > Confirm there is no Default browser prompt is shown
• Go to device settings and update the date to be 8 days from today
• Close and relaunch Brave > Confirm that Default browser prompt is shown on regular NTP
• Open another NTP until you see SI page > Observe

Screenshots:

RPReplay_Final1694195839.MP4

Reviewer Checklist:

• Issues include necessary QA labels:
  • QA/(Yes|No)
  • bug / enhancement
• Necessary security reviews have taken place.
• Adequate unit test coverage exists to prevent regressions.
• Adequate test plan exists for QA to validate (if applicable).
• Issue and pull request is assigned to a milestone (should happen at merge time).