Add tests for pii redaction

[sanason]

A few integration tests for PII redaction, mostly testing that redaction is applied in the correct circumstances. These are not intended to fully exercise the redaction algorithms. Once these integration tests are in place, I'd like to refactor the redaction function so it can be unit tested and build a more complete unit test suite.

• PII redaction is applied to the event parameters in a gtag('event', '<event_name>', {<event_params>}) call. Tests for email, SSN, phone number, DOB, and password redaction.
• PII redaction is applied to the additional config info in a gtag('config', '<TARGET_ID>', {<additional_config_info>}) call.
• PII redaction also applies to GA4 automatically collected events, which DAP implements by adding a PII-redacting wrapper to the window.navigator.sendBeacon call.