Optionally store self-hosted Edge Functions in S3

Storing Edge Functions in S3 will enable easy editing (through Supabase Studio) for deployment across multiple servers. Currently, the same volume must be mounted in Supabase Studio and Edge Functions, meaning they must be located on the same host. Using S3 for storage means the functions can be pulled in from any server, enabling high-availability and the ability to truly run functions on the edge.