Support `terminal.integrated.rightClickBehavior` configuration

[kittaakos]

terminal.integrated.rightClickBehavior is currently unsupported by Theia.

When I add the terminal.integrated.rightClickBehavior to the settings.json, I see a warning:

Property terminal.integrated.rightClickBehavior is not allowed.

Feature Description:

terminal.integrated.rightClickBehavior configuration is supported in Theia.