Event logs: allow logging URLs from all sourcegraph domains in local event logs

Created by: camdencheek

This updates the local event log URL redaction code to allow any URLs ending in sourcegraph.com to be logged. Note that when sending event logs to BigQuery, we redact all https://sourcegraph.com URLs so that private information isn't leaving the cluster, however that isn't a concern for local event logs.

Test plan

Added unit test that documents a few cases of how this should work.