fix: IDENTIFY_EVENT renamed to prevent symbol collision

[omarzl]

Summary

When we compile Amplitude and Rakam and we link them statically we have a symbol collision as shown in this image:

This causes that the linker selects one of the two, in this example it selected Rakam's one: $$user

This is causing us that Amplitude considers it as any other event instead of setting user properties:

Checklist

• [X] Does your PR title have the correct title format?
• Does your PR have a breaking change?: No