Fix ( Fatal Issue TypeError: Cannot read property '_objectKey' of undefined #6925 )

[Ashik55]

What, How & Why?

This closes # ???

☑️ ToDos

• 📝 Changelog entry
• 📝 Compatibility label is updated or copied from previous entry
• 📝 Update COMPATIBILITY.md
• 🚦 Tests
• 📦 Updated internal package version in consuming package.jsons (if updating internal packages)
• 📱 Check the React Native/other sample apps work if necessary
• 💥 Breaking label has been applied or is not necessary
• 🔔 Mention @realm/devdocs if documentation changes are needed

[cla-bot]

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[kraenhansen]

Thanks for your PR. To ensure this problem doesn't regress, I'd be very interested in getting a better understanding and an actual test reproducing it. Would you be willing to investigate this further?