Add unit tests for retry flow in HttpApiService

[mikejancar]

🚀 Feature request

Please describe what is needed

Ideally, we would have unit tests that cover the retry functionality in the HttpApiService

Describe the solution you'd like

We were never able to get these to work due to the complexity of having the call fail, wait in the test and then retry. I'm sure this is doable, but it requires a deeper dive in how to attack this use case.

Describe alternatives you've considered

N/A

Additional context

https://github.com/Progressive/oculr-ngx/blob/c15535ade25ab5b8398890fa0411d1b6098c324b/projects/oculr-ngx/src/lib/destinations/http-api/http-api.service.spec.ts#L132

https://github.com/Progressive/oculr-ngx/blob/c15535ade25ab5b8398890fa0411d1b6098c324b/projects/oculr-ngx/src/lib/destinations/http-api/http-api.service.spec.ts#L156