end-to-end testing of CT log workflows

**Description**

[Noted here](https://github.com/sigstore/rekor-monitor/blob/48375db9da425b4d9985ca13cb9f854b4f59439d/pkg/ct/consistency_test.go#L33): end-to-end testing for certificate transparency log monitoring should test the functionality of both the consistency check and the identity monitoring more thoroughly than the current mocked tests.