Terminal suggest partial `selectionMode` contrast issue

[meganrogge]

From @kieferrm

On the Light+ theme, there's a contrast issue where the font of the completion item has very low contrast with the foreground. This might be related to the this._suggestWidget.list.style( calls in TerminalSuggestAddon.

[meganrogge]

The issue is for that theme, this color is white:

When I change it to red:

When I uncheck that rule:

[meganrogge]

it's white in that theme because expects there will be a blue background...