fix: additional config validations

[threepointone]

I remembered some more validations we had to add, making a list here, will add as I think of more -

• All the binding names should be distinct, no repeats (since they'll all be hanging off the same env object) #658
• Having both route and routes in config should throw an error #629
• We should error when a user tries to implement a durable object in a worker using the service-worker format #635
• We should deprecate being able to pass every config value as CF_ env vars (which is possible in wrangler 1!!) #657