"Loading citation data..." persists if there's no entities data

[andrewhead]

If the API returns no entities for a paper, then the loading bar for citation data that reads "Loading citation data..." appears indefinitely. The ideal behavior might be to not show the "Loading citation data..." bar if no citation entities were retrieved from the API.

See this bug in action here:

https://scholarphi.semanticscholar.org/?file=https://arxiv.org/pdf/2009.14237.pdf&preset=demo