Ensuring Hyrax::UserStatImporter returns false on exception
Ensuring Hyrax::UserStatImporter returns false on exception

Prior to this commit, in the retriable block, if we hit an exception,
we'd return `true` and upstream we'd raise an exception.

In the below code, the `extract_stats_for` is returning true, because
calls to `Rails.logger.info` return true.

```ruby
view_stats = extract_stats_for(object: file, from: FileViewStat, start_date: start_date, user: user)
stats = tally_results(view_stats, :views, stats) if view_stats.present?
```

This resulted in attempting to call `.each` on the `view_stats`; which
was true.

This builds on a [reported issue in Slack][1].

Closes #5873

[1]:https://samvera.slack.com/archives/C0F9JQJDQ/p1663608069939129

samvera/hyrax,samvera/hyrax,samvera/hyrax,samvera/hyrax