Admin interface Filter component accessibility shortcomings

[svenaas]

The Filter component (Svelecte) — displayed at the top of many admin interface screens — could use some accessibility improvement. Specifically, there are no form field labels for the text input box and the hidden select. There's some ARIA in there (to indicate hidden and collapsed states) but it doesn't look like it mitigates the basic problem of ensuring all users can understand and use this component.

Notes

• Found during cloud-gov/product#2497 which was a spot check survey and not a thorough review of all pages and components; there may be additional issues.

Acceptance Criteria

• [ ] WAVE scan of admin interface pages no longer reports errors on missing field labels for the filter component.