resolve test flake on evaluateJavascript

[kiftio]

What changes are you making?

Fixed flakiness by removing the async wait

The issue was the test observed WKWebView.evaluateJavaScript through a mock override and XCTest expectation, which made the assertion depend on WebKit scheduling.

Added an internal closure-backed overload in CheckoutBridge.swift, kept the real WKWebView call path unchanged, and updated CheckoutBridgeTests.swift to assert the generated JavaScript synchronously.

The now-unused MockWebView.swift was deleted.

How to test

dev swift test CheckoutBridgeTests

Before you merge

Important

• I've added tests to support my implementation
• I have read and agree with the Contribution Guidelines
• I have read and agree with the Code of Conduct
• I've updated the relevant platform README (platforms/swift/README.md and/or platforms/android/README.md)

---

Releasing a new Swift version?

• I have bumped the version in ShopifyCheckoutKit.podspec
• I have bumped the version in platforms/swift/Sources/ShopifyCheckoutKit/ShopifyCheckoutKit.swift
• I have updated platforms/swift/CHANGELOG.md
• I have updated the SwiftPM/CocoaPods version snippets in platforms/swift/README.md (major version only)

Releasing a new Android version?

• I have bumped the versionName in platforms/android/lib/build.gradle
• I have updated platforms/android/CHANGELOG.md
• I have updated the Gradle/Maven version snippets in platforms/android/README.md

Tip

See the Contributing documentation for the full release process per platform.

[github-actions]

React Native — Coverage Report

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[Juanita-Dash]

LGTM