The SignalR integration from Azure Functions does not have automatic retry. When the SignalR instance has issues, all other APIs fail.
To make the service resilient to SignalR outages, this bounces SignalR events through an Azure Storage queue.
NOTE: This PR does not remove the integration from all of the functions. That is intended to be done as a follow-on PR.
We're experiencing a bug where Unions of sub-models are getting downcast, which causes a loss of information.
As an example, EventScalesetCreated was getting downcast to EventScalesetDeleted. I have not figured out why, nor can I replicate it locally to minimize the bug send upstream, but I was able to reliably replicate it on the service.
While working through this issue, I noticed that deserialization of SignalR events was frequently wrong, leaving things like tasks as "init" in `status top`.
Both of these issues are Unions of models with a type field, so it's likely these are related.
## Summary of the Pull Request
_What is this about?_
Due to our GDPR privacy requirements, we decided that it would be best to completely purge personal identifiable information from our AppInsights telemetry and logging. Instead of just removing all of the logging statements with personal info, I created a filter function that logs telemetry after it's been run through a recursive scrubbing function. This PR includes this new scrubbing function.
## PR Checklist
* [x] Applies to work item: #660
* [ ] CLA signed. If not, go over [here](https://cla.opensource.microsoft.com/microsoft/onefuzz) and sign the CLI.
* [ ] Tests added/passed
* [ ] Requires documentation to be updated
* [x] I've discussed this with core contributors already. If not checked, I'm ready to accept this work might be rejected in favor of a different grand plan. Issue number where discussion took place: #xxx
## Info on Pull Request
_What does this include?_
Includes changes to events.py in onefuzzlib. I've implemented functionality - log_event() - to recursively check Event structures for UserInfo before logging to AppInsights.
## Validation Steps Performed
I run local tests using a script I created with test events.
_How does someone test & validate?_
I can provide local testing script. If that is insufficient, I can write a unit test that will run against this code.
