Filter: Neighborhoods/Community Org/Zone Pills: Unable to clear the pills using screen readers

## Description
Tracy Note: This ticket is related to https://github.com/CodeForPhilly/clean-and-green-philly/issues/631 & probably would be fixed with that refactor to pull out the selected pills from the dropdown.

Clearing the pills is impossible using NVDA & Voice Over. JAWS is more forgiving.

- NVDA + FF/Edge: Using tab key to navigate to the X button, selecting it activates the listbox pop up instead

Demo; see **from point 2:18** of the video onwards.

https://github.com/CodeForPhilly/clean-and-green-philly/assets/102739972/ade5b3b2-ca41-4165-ac9f-6bbbb8ca462c

- VO + Safari: Screen reader focus could not navigate to the pills at all; no feedback given when tabbing to it.

## Recommendation
- Would be better to not put the pill on top of the listbox popup so that there's a clear separation between the 2. It will also make the UI less confusing even for sighted users.

Start by reproducing the filter-pill behavior with NVDA on Firefox/Edge and VoiceOver on Safari, using issue 631 for the related refactor context. Done means screen-reader users can reach, understand, and clear the Neighborhoods, Community Org, and Zone pills without activating the listbox unexpectedly.

Written by the indexing model from the issue text.