chore(simdv2): allow overriding the --home flag

There were two calls to viper.Set(serverv2.FlagHome,
simapp.DefaultNodeHome); these calls invalidated any provided --home
command line arguments. When testing multiple simapp instances in the
same process, it is necessary to provide separate home directories.

Changing the calls from .Set to .SetDefault retains the previous
behavior of using DefaultNodeHome when no --home flag is provided, but
it still respects --home when the flag is indeed provided.

Author: mark-rushakoff

simapp/v2/simdv2/cmd/commands.go

@@ -37,7 +37,7 @@ import (
 )
 
 func newApp[T transaction.Tx](logger log.Logger, viper *viper.Viper) serverv2.AppI[T] {
-	viper.Set(serverv2.FlagHome, simapp.DefaultNodeHome)
+	viper.SetDefault(serverv2.FlagHome, simapp.DefaultNodeHome)
 	return serverv2.AppI[T](simapp.NewSimApp[T](logger, viper))
 }
 
@@ -165,7 +165,7 @@ func appExport[T transaction.Tx](
 
 	// overwrite the FlagInvCheckPeriod
 	viper.Set(server.FlagInvCheckPeriod, 1)
-	viper.Set(serverv2.FlagHome, simapp.DefaultNodeHome)
+	viper.SetDefault(serverv2.FlagHome, simapp.DefaultNodeHome)
 
 	var simApp *simapp.SimApp[T]
 	if height != -1 {