fix(ui): checks truthy value for last ingested

[pinakipb2]

Checklist

• The PR conforms to DataHub's Contributing Guideline (particularly Commit Message Format)
• Links to related issues (if applicable)
• Tests for the changes have been added/updated (if applicable)
• Docs related to the changes have been added/updated (if applicable). If a new feature has been added a Usage Guide has been added for the same.
• For any breaking change/potential downtime/deprecation/big changes an entry has been made in [Updating DataHub](https://github.com/datahub-project/datahub/blob/master/docs/how/updating-datahub.md

When lastIngested is 0, 0 gets rendered on the screen.