Public catalog view sort-dropdown options need accessible labels for screen readers #7235

Descriptive summary

In the public catalog view, sort-dropdown options are currently:

• relevance
• date uploaded ▼
• date uploaded ▲
• date modified ▼
• date modified ▲

The triangle symbols read as "triangle" to screen readers and should read as "descending" and "ascending"

Steps to reproduce the behavior in User Interface (UI)

1. Use a screen reader to view your Hyrax application (Windows: Narrator, NVDA, or JAWS; Mac: VoiceOver)
2. Navigate to catalog view (/catalog)
3. Expand the Sort By button to see available options
4. Note how "triangle" is stated rather than "ascending" and "descending"

Acceptance Criteria/Expected Behavior

• Screen readers read "ascending" and "descending" instead of "triangle" for sort options, e.g. "date uploaded descending"

Rationale

Sort options currently can't be differentiated in a screen reader.