fix(apple): remove sentry frames from stacktrace (testing only)

[buenaflor]

:scroll: Description

Before fix:

After fix:

:bulb: Motivation and Context

Fixes https://github.com/getsentry/sentry-kotlin-multiplatform/issues/77

:green_heart: How did you test it?

Unit tests

:pencil: Checklist

You have to check all boxes before merging:

• [ ] I reviewed the submitted code.
• [ ] I added tests to verify the changes.
• [ ] No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
• [ ] I updated the docs if needed.
• [ ] Review from the native team if needed.
• [ ] No breaking change or entry added to the changelog.

:crystal_ball: Next steps