chip: fix group keyboard operability in Firefox

[hellogreg]

Description of the issue

Chip groups are not currently arrow-key-operable in Mac and Windows Firefox.

Impacted component(s)

• pf-chip
• pf-chip-group

Steps to reproduce

1. Go to chip documentation.
2. Navigate to a chip group using the tab key.
3. Try using the arrow keys to navigate between chips.

The arrows don't move focus between the chips themselves. However, if you hit the arrow key enough times, focus will move to the x more/show less chip. (Focus then sticks on this chip until the tab key is pressed. The arrows no longer do anything.)

Tested in Firefox 115 (ESR) and 122.

Expected behavior

The user can navigate between all chips in a chip group via the arrow keys.

[bennypowers]

@hellogreg can we close this?