[CSLD-162] Remove obsolete README info
[CSLD-162] Remove obsolete README info

We switch from the default / official Swagger visualization to ReDoc which doesn't support trying
out endpoints directly in the browser (yet).

input-output-hk/cardano-sl,input-output-hk/cardano-sl,input-output-hk/pos-haskell-prototype,input-output-hk/cardano-sl,input-output-hk/cardano-sl,input-output-hk/pos-haskell-prototype,input-output-hk/pos-haskell-prototype