Fix shared example for Internal Events Tracking

What does this MR do and why?

While working on the quick-start guide I realized that our shared example doesn't allow us to verify that tracking works if no user is provided.

Tracking events without a user is a valid use-case, so we should support that.

This MR fixes that.

MR acceptance checklist

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• I have evaluated the MR acceptance checklist for this MR.

Related to #415446 (closed)