cardano-testnet: disable ExperimentalHardForksEnabled in default config

After ProtVer 12 became the experimental-gated version, Conway-era
testnets forged blocks with PV 12 in the header, which the Conway
BBody rule rejects (max PV = 11). Dropping the unconditional flag
from hardforkViaConfig makes the node fall back to ProtVer 11, which
Conway accepts, so the testnet chain progresses.

Author: Jimbo4350

cardano-testnet/src/Testnet/Defaults.hs

@@ -219,8 +219,7 @@ defaultYamlHardforkViaConfig sbe =
   hardforkViaConfig :: ShelleyBasedEra era -> Aeson.KeyMap Aeson.Value
   hardforkViaConfig sbe' =
     Aeson.fromList $
-      [ ("ExperimentalHardForksEnabled", Aeson.Bool True)
-      , ("ExperimentalProtocolsEnabled", Aeson.Bool True) ]
+      [ ("ExperimentalProtocolsEnabled", Aeson.Bool True) ]
       ++ (case sbe' of
             ShelleyBasedEraShelley ->
                 [ ("TestShelleyHardForkAtEpoch", Aeson.Number 0) ]

cardano-testnet/test/cardano-testnet-golden/files/golden/node_default_config.json

@@ -5,7 +5,6 @@
     "DijkstraGenesisFile": "dijkstra-genesis.json",
     "EnableLogMetrics": false,
     "EnableLogging": true,
-    "ExperimentalHardForksEnabled": true,
     "ExperimentalProtocolsEnabled": true,
     "LastKnownBlockVersion-Alt": 0,
     "LastKnownBlockVersion-Major": 9,