Fix brave-browser #36266: Buy/Send/Swap button is not opening in Asset Details Screen.

[nuo-xu]

Ref:
brave/brave-core#22229

Summary of Changes

Copy over the fix from brave-core to brave-ios for 1.62.x hotfix.

This pull request fixes #

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:

Go to an asset details that no wallet account has balance of it
click Buy/Send/Swap button
button should open correct screen for users to buy/send/swap

Screenshots:

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).