Work around "useNativeDriver" was not specified warning

Since upgrading the Expo SDK version in 12a3d2fc there is a warning that keeps appearing when displaying toasts:

backend.js:32 Animated: `useNativeDriver` was not specified. This is a required option and must be explicitly set to `true` or `false`

As indicated by this issue it's an upstream bug, though it appears to be worked around in newer versions of native-base. It might be possible to fix either by upgrading native-base, or just setting the warning to be ignored.