Summary:
Since the `hot` parameter is not used anymore in metro-bundler (we are always applying the HMR transforms for bundlers requested through the HTTP server), we can remove it from the client request URL.
This allows us to reduce the metro-bundler memory by half when switching between HMR and not-HMR, since metro caches the bundles based on the requested URL path.
Reviewed By: davidaurelio
Differential Revision: D5630051
fbshipit-source-id: fb5dce4c31bbb38b1c0c93c97a525a992b2f6d8d