UI improvements to the BioontologySelectView & BioontologyBrowserView

[robyngit]

With PR #2502, we're adding two new bioontology views that allow flexibly searching for and selecting classes from multiple ontologies. The views can be configured to use any ontology that's on the Bioportal.

There are a few further improvements I think we could make after the initial release, listed and illustrated below:

BioontologySelectView

• Show the configured ontology icon next to each ontology & class in the dropdown
• Use the configured ontology label in the dropdown instead of the acronym
• Add a tooltip to the ontologies in the dropdown (which act as category headers) to show the description of the ontology and the acronym
• Show more information in the tooltip for each class, including the class ID. Visually differentiate between the description and the number of datasets that use the term (currently just appended to the description).
• Many terms that exist in the data catalog are not found in the common ontologies that we configure in the app. These terms are added to the "unknown ontology" category and their class ID is displayed instead of the more human-readable label. We can't do a batch search unless we know the ontology, but we could search for them one-by-one when the user first hovers over the term. This would allow us to display the label without too many extra API calls.

Bioontology Browser

• Add a search to the top of the Bioontology browser to filter classes in the accordion
• Add a filter to the Bioontology browser to hide all classes that are not used by any datasets in the catalog
• Add a help button to the Bioontology browser that links to another page or a modal with more information about ontologies and links to the Bioportal documentation
• Display the number datasets that use each class next to the class name (information we've already fetched in the BioontologySelectView).
• Add a dropdown icon next to the ontology switcher to make it more obvious that it's a dropdown (I'm worried users might not realize they can switch ontologies, needs testing).