use current mainnet value as tx max size in unit test

  So that we get some order good of magnitudes when it comes to what can be expected for Mainnet.

lib/shelley/test/unit/Cardano/Wallet/Shelley/TransactionSpec.hs

@@ -152,11 +152,11 @@ spec = do
         prop "roundtrip for Byron witnesses" prop_decodeSignedByronTxRoundtrip
 
     estimateMaxInputsTests @ShelleyKey
-        [(1,27),(5,17),(10,12),(20,0),(50,0)]
+        [(1,114),(5,104),(10,99),(20,75),(50,34)]
     estimateMaxInputsTests @ByronKey
-        [(1,17),(5,10),(10,6),(20,0),(50,0)]
+        [(1,73),(5,66),(10,62),(20,45),(50,16)]
     estimateMaxInputsTests @IcarusKey
-        [(1,17),(5,10),(10,6),(20,0),(50,0)]
+        [(1,73),(5,66),(10,62),(20,45),(50,16)]
 
     describe "fee calculations" $ do
         let pp :: ProtocolParameters
@@ -424,7 +424,7 @@ estimateMaxInputsTests cases = do
             it ("order of magnitude, nOuts = " <> o <> " => nInps = " <> i) $ do
                 let outs = [ generatePure r arbitrary | r <- [ 1 .. nOuts ] ]
                 length outs `shouldBe` nOuts
-                _estimateMaxNumberOfInputs @k (Quantity 4096) defaultTransactionCtx outs
+                _estimateMaxNumberOfInputs @k (Quantity 16384) defaultTransactionCtx outs
                     `shouldBe` nInps
 
         prop "more outputs ==> less inputs"