This caused a build error when Forget was used in an Expo app as the
react-forget-runtime package was itself being compiled with Forget. This broke
Metro as metro serializes modules to iifes, but the import syntax that was
injected by the useMemoCachePolyfill flag was left behind
In practice I don't think the runtime package needs to ever be compiled by
Forget, so this PR opts out the whole file. This would also prevent builds from
breaking if someone decided to use the "all" compilation mode.
Test plan: Ran the expo app and verified that it now builds with no errors