refactor: remove auth and logging middleware

This commit removes auth middleware for it hides
side effects and obscures logic. The auth operations
are now done in its own stage in the request-response
cycle.

It also removes the logging middleware because now
we instead use observation module to log the response.

src/PostgREST/Observation.hs

@@ -16,6 +16,7 @@ import qualified Hasql.Connection           as SQL
 import qualified Hasql.Pool                 as SQL
 import qualified Hasql.Pool.Observation     as SQL
 import           Network.HTTP.Types.Status  (Status)
+import qualified Network.Wai                as Wai
 import           PostgREST.Config.PgVersion
 import           PostgREST.Query            (MainQuery)
 import           PostgREST.SchemaCache      (QueryTimings)
@@ -52,6 +53,7 @@ data Observation
   | PoolInit Int
   | PoolAcqTimeoutObs
   | HasqlPoolObs SQL.Observation
+  | ResponseObs (Maybe ByteString) Wai.Request Status (Maybe Integer)
   | PoolRequest
   | PoolRequestFullfilled
   | PoolFlushed