Remove all tests and dependencies from test project

This commit removes all test methods from `FileAggregateDomainEventTests.cs` and `FileImportLogAggregateDomainEventTests.cs`, resulting in a significant reduction in test coverage for domain events related to file processing and import logs. Additionally, all package and project references have been removed from `FileProcessor.DomainEvents.Tests.csproj`, leaving the test project without necessary dependencies.

Author: StuartFerguson