Latest Only option for Historical Retrieval

**Is your feature request related to a problem? Please describe.**

In many batch workflows, it is worthwhile to retrieve the latest features by entity only. This is useful from the purposes of both production and backtesting purposes.

E.g. if I have an hourly/daily batch which goes through our whole customer base to find fraudulent customers, we wouldn't really use the online store for this.

**Describe the solution you'd like**

Allow users to specify an entity set extracted from a feature view should have an option to be deduplicated by `latest`. Depends on #1611

```
my_daily_batch_scoring_df = store.get_latest_features(
entity_df = "my_df",
feature_refs = [...],
)
```

**Additional context**
Linked issue #1611