Support log assertions

[Silic0nS0ldier]

While this can be done manually, it is a bit of a PITA. We already require the execution context as an input, we might as well expand the scape as that is a requirement which won't change anytime soon (that is, unless in the future something like https://github.com/SimonCropp/XunitContext is supported).

[Silic0nS0ldier]

Notes

Desired functionality could include;

• Specific log events appearing in the desired order
• Various permutations on the above with more forgiving checks or ordering forgiveness
• No log events
• Automatic assertion check on test completion (can be surprisingly difficult, so usually its easier to just do an explicit check)

Potential problems include;

• Logging being non-blocking action (async)
• Log events having entropy (e.g. ID and timestamps)
• Keeping checks DRY without risking self-validation (e.g. using implementation logic to generate a value)
• Dealing with log event noise from components outside the scope of what you are testing