Investigate update tab issues (updates made at different times share the same log, etc.) #1259

It seems that updating an entity twice (saving in between) sometimes makes the updates appear in a single log inside the Updates tab. I've done some quick testing for Localities and Occurrences, but it's likely that this is a problem for any entity. This also does not seem to happen 100% of the time, but making the updates in quick succession or refreshing the page in between the updates might have something to with it. Maybe updates made in the span of one minute results in both updates having the same timestamp, which makes them group together? EDIT: This should be fixed with #1241 , the problem was that edits made on the same day were sometimes grouped together in the frontend, although they are separate in the backend.

To test:

1. Go to a locality's details
2. Update any value and save the locality
3. Go to the update tab, the update details should show up normally
4. Update a different value and save the locality
5. Go to the update tab, check if there is still only a single update log that shows both updates

Also, making an update to a value, saving it, then reverting the value to the original value and saving again seems to remove the update log for the change entirely, instead of creating a total of two update logs, like it probably should. Again, this happened for both a Locality and an Occurrence.

To test:

1. Go to a locality's details
2. Update any value and save the locality
3. Go to the update tab, the update details should show up normally
4. Revert the same value to its original value and save the locality
5. Go to the update tab, check if the update log no longer exists