* Remove legacy GitHub API cache of HRA.Status.CachedEntries
We migrated to the transport-level cache introduced in #1127 so not only this is useless, it is harder to deduce which cache resulted in the desired replicas number calculated by HRA.
Just remove the legacy cache to keep it simple and easy to understand.
* Deprecate githubAPICacheDuration helm chart value and the --github-api-cache-duration as well
* Fix integration test
The log level -3 is the minimum log level that is supported today, smaller than debug(-1) and -2(used to log some HRA related logs).
This commit adds a logging HTTP transport to log HTTP requests and responses to that log level.
It implements http.RoundTripper so that it can log each HTTP request with useful metadata like `from_cache` and `ratelimit_remaining`.
The former is set to `true` only when the logged request's response was served from ARC's in-memory cache.
The latter is set to X-RateLimit-Remaining response header value if and only if the response was served by GitHub, not by ARC's cache.