fix(experimental-utils): make keys for ReferenceTracker options optional

[MageJohn]

Fixes #3526

[typescript-eslint]

Thanks for the PR, @MageJohn!

typescript-eslint is a 100% community driven project, and we are incredibly grateful that you are contributing to that community.

The core maintainers work on this in their personal time, so please understand that it may not be possible for them to review your work immediately.

Thanks again!

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[nx-cloud]

Nx Cloud Report

CI ran the following commands for commit 1a0f33c. Click to see the status, the terminal output, and the build insights.

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	nx run-many --target=build --all --parallel
	nx run-many --target=typecheck --all --parallel

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[MageJohn]

Not sure how to resolve the Semantic Pull Request failure; let me know and I'll get it done!

[bradzacher]

thanks!