Add StateSpec tests for increment tx

Currently failing because of missing script input so we need to
make sure to provide all needed UTxO when generating txs.

hydra-node/test/Hydra/Chain/Direct/StateSpec.hs

@@ -66,6 +66,7 @@ import Hydra.Chain.Direct.State (
   genDepositTx,
   genFanoutTx,
   genHydraContext,
+  genIncrementTx,
   genInitTx,
   genRecoverTx,
   genStInitial,
@@ -348,6 +349,10 @@ spec = parallel $ do
           Nothing ->
             False & counterexample ("observeRecoverTx ignored transaction: " <> renderTxWithUTxO utxo tx)
 
+  describe "increment" $ do
+    propBelowSizeLimit maxTxSize forAllIncrement
+    propIsValid forAllIncrement
+
   describe "decrement" $ do
     propBelowSizeLimit maxTxSize forAllDecrement
     propIsValid forAllDecrement
@@ -655,6 +660,23 @@ forAllRecover ::
 forAllRecover action = do
   forAllShrink genRecoverTx shrink $ uncurry action
 
+forAllIncrement ::
+  Testable property =>
+  (UTxO -> Tx -> property) ->
+  Property
+forAllIncrement action = do
+  forAllIncrement' $ \_ utxo tx ->
+    action utxo tx
+
+forAllIncrement' ::
+  Testable property =>
+  ([TxOut CtxUTxO] -> UTxO -> Tx -> property) ->
+  Property
+forAllIncrement' action = do
+  forAllShrink (genIncrementTx maximumNumberOfParties) shrink $ \(ctx, committed, st, incrementUTxO, tx) ->
+    let utxo = getKnownUTxO st <> getKnownUTxO ctx <> incrementUTxO
+     in action committed utxo tx
+
 forAllDecrement ::
   Testable property =>
   (UTxO -> Tx -> property) ->