refactor: move getConnectedFieldForReferences to separate function

[dpilch]

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• [ ] PR description included
• [ ] yarn test passes
• [ ] Tests are changed or added
• [ ] Relevant documentation is changed or added (and PR referenced)
• [ ] Breaking changes to existing customers are released behind a feature flag or major version update
• [ ] Changes are tested using sample applications for all relevant platforms (iOS/android/flutter/Javascript) that use the feature added/modified
• [ ] Changes are tested on windows. Some Node functions (such as path) behave differently on windows.

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