Add flag to skip integrated driver tests (#2884)
Add flag to skip integrated driver tests (#2884)

This can be used in cases where the compiler being used isn't compatible
with the integrated driver. By default, we will still run the test with
the integrated driver as well.
apple/swift-package-manager,apple/swift-package-manager,apple/swift-package-manager,abertelrud/swift-package-manager,abertelrud/swift-package-manager,apple/swift-package-manager,abertelrud/swift-package-manager,abertelrud/swift-package-manager,apple/swift-package-manager,abertelrud/swift-package-manager