refactor: clarify usage of genesis.TxHandler in v1 vs v2 (backport #21213) (#21218)

Co-authored-by: Julien Robert <julien@rbrt.fr>

runtime/module.go

@@ -15,7 +15,6 @@ import (
 	"cosmossdk.io/core/app"
 	"cosmossdk.io/core/appmodule"
 	"cosmossdk.io/core/comet"
-	"cosmossdk.io/core/genesis"
 	"cosmossdk.io/core/legacy"
 	"cosmossdk.io/core/store"
 	"cosmossdk.io/depinject"
@@ -29,6 +28,7 @@ import (
 	"github.com/cosmos/cosmos-sdk/std"
 	"github.com/cosmos/cosmos-sdk/types/module"
 	"github.com/cosmos/cosmos-sdk/types/msgservice"
+	"github.com/cosmos/cosmos-sdk/x/genutil"
 )
 
 // appModule defines runtime as an AppModule
@@ -240,7 +240,7 @@ func ProvideModuleManager(modules map[string]appmodule.AppModule) *module.Manage
 	return module.NewManagerFromMap(modules)
 }
 
-func ProvideGenesisTxHandler(appBuilder *AppBuilder) genesis.TxHandler {
+func ProvideGenesisTxHandler(appBuilder *AppBuilder) genutil.TxHandler {
 	return appBuilder.app
 }