Improve exception handling of Zebra calls

This PR allows for the Zebra behavior of not having a `result` field in the RPC response on error conditions.

Reviewed-on: #40
Co-authored-by: Rene Vergara <rene@vergara.network>
Co-committed-by: Rene Vergara <rene@vergara.network>

src/ZcashHaskell/Utils.hs

@@ -23,7 +23,7 @@ import C.Zcash
   , rustWrapperF4Jumble
   , rustWrapperF4UnJumble
   )
-import Control.Exception (try)
+import Control.Exception (SomeException(..), try)
 import Control.Monad.IO.Class
 import Data.Aeson
 import qualified Data.ByteString as BS
@@ -91,7 +91,7 @@ makeZebraCall host port m params = do
         setRequestMethod "POST" defaultRequest
   r <-
     try $ httpJSON myRequest :: FromJSON a1 =>
-      IO (Either HttpException (Response (RpcResponse a1)))
+      IO (Either SomeException (Response (RpcResponse a1)))
   case r of
     Left ex -> return $ Left $ show ex
     Right res -> do