fix(firebase_analytics): allow `logEvent` to accept `items` inside `parameters`

[nikitadol]

Description

Before this PR: logEvent did not accept items inside parameters After this PR: logEvent can accept items inside parameters

Reason for this PR: On my project, our backend can send all data for analytics event, including items - this PR extends checks in _assertParameterTypesAreCorrect to allow this behavior

Related Issues

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