Reserve red as a button color for dangerous actions

Glenn from OnionShare has rightly pointed out that we should reserve red for dangerous and/or destructive buttons only. There are two instances in Tor Browser 11.5 that we're using it for non-dangerous, recommended actions:

• Connection Assist's location check error: location-check-light
• Connection Settings' red message bar: connection-error-dark

We should consider alternatives to red for these actions.