Move test helper methods to common

[jwrosewell]

There is duplicate code between ExampleUtils.cs and FiftyOne.IpIntelligence.TestHelpers/Utils.cs. This code should be moved to common-dotnet and used across examples and tests. There may be other examples of code copying that should be eliminated.

[jwrosewell]

@justadreamer assigned to you in the first instance to pass to an engineer to refactor.