fix: Infinite recursion when custom config is used

[einsteinx2]

Summary

• Due to a logic error, any time a customer would supply a customer Iterable config and a URL was handled, it would get into an infinite recursion loop and blow up the stack. The logic has been corrected and now works as expected (we forward to the customer's url delegate instead of to ourselves).

Testing Plan

• Tested end to end with the TSE to ensure the behavior is now correct when using a custom config and real Iterable push notifications. We first reproduced it using the old version by passing a custom config, then updated to this branch and saw that it is now handled correctly.

Reference Issue (For mParticle employees only. Ignore if you are an outside contributor)

• Closes https://go.mparticle.com/work/SQDSDKS-4987

[BrandonStalnaker]

LGTM