Report suppressed exceptions as exception group

[adinauer]

📜 Description

Report exceptions returned by Throwable.getSuppressed() to Sentry as exception groups. They show up like this:

Links can be clicked and take you to the exception on the same page.

💡 Motivation and Context

Fixes #542

💚 How did you test it?

📝 Checklist

• 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.
• No breaking change for hybrid SDKs or communicated to hybrid SDKs.

🔮 Next steps