[SB][Chips] Add custom a11y click label for notification chips.

Makes the "Double tap to activate" accessibility label more specific
for just the notification chips.

Fixes: 412479163
Bug: 364653005
Flag: com.android.systemui.status_bar_chips_modernization
Test: Trigger notification chip -> verify a11y text includes "Double tap
to expand notification"
Test: Trigger notification chip then tap on it, then re-focus on chip ->
verify a11y text includes "Double tap to collapse notification"
Test: Trigger screen record chip -> verify a11y text is the default
"Double tap to activate"
Test: Trigger call chip -> verify a11y text is the default "Double tap
to activate"
Test: Without TalkBack, verify you can tap the chip to toggle the
notification state like before

Change-Id: Ifc4ff7bd6fc0f8c31e0f1d8d3c8e5aea30b23552