feat: add x/group app wiring integration tests (#12243)

## Description

ref: #12024 



---

### Author Checklist

*All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues.*

I have...

- [ ] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
- [ ] targeted the correct branch (see [PR Targeting](https://github.com/cosmos/cosmos-sdk/blob/main/CONTRIBUTING.md#pr-targeting))
- [ ] provided a link to the relevant issue or specification
- [ ] followed the guidelines for [building modules](https://github.com/cosmos/cosmos-sdk/blob/main/docs/building-modules)
- [ ] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/main/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] included comments for [documenting Go code](https://blog.golang.org/godoc)
- [ ] updated the relevant documentation or specification
- [ ] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

*All items are required. Please add a note if the item is not applicable and please add
your handle next to the items reviewed if you only reviewed selected items.*

I have...

- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed 
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

testutil/network/network.go

@@ -25,6 +25,7 @@ import (
 	"google.golang.org/grpc"
 
 	"cosmossdk.io/math"
+
 	"github.com/cosmos/cosmos-sdk/baseapp"
 	"github.com/cosmos/cosmos-sdk/client"
 	"github.com/cosmos/cosmos-sdk/client/tx"
@@ -135,35 +136,37 @@ func DefaultConfigWithAppConfig(appConfig depinject.Config) (Config, error) {
 
 	var (
 		appBuilder        *runtime.AppBuilder
-		msgServiceRouter  *baseapp.MsgServiceRouter
 		txConfig          client.TxConfig
 		legacyAmino       *codec.LegacyAmino
-		codec             codec.Codec
+		cdc               codec.Codec
 		interfaceRegistry codectypes.InterfaceRegistry
 	)
 
 	if err := depinject.Inject(appConfig,
 		&appBuilder,
-		&msgServiceRouter,
 		&txConfig,
-		&codec,
+		&cdc,
 		&legacyAmino,
 		&interfaceRegistry,
 	); err != nil {
 		return Config{}, err
 	}
 
-	cfg.Codec = codec
+	cfg.Codec = cdc
 	cfg.TxConfig = txConfig
 	cfg.LegacyAmino = legacyAmino
 	cfg.InterfaceRegistry = interfaceRegistry
 	cfg.GenesisState = appBuilder.DefaultGenesis()
 	cfg.AppConstructor = func(val Validator) servertypes.Application {
+		// we build a unique app instance for every validator here
+		var appBuilder *runtime.AppBuilder
+		if err := depinject.Inject(appConfig, &appBuilder); err != nil {
+			panic(err)
+		}
 		app := appBuilder.Build(
 			val.Ctx.Logger,
 			dbm.NewMemDB(),
 			nil,
-			msgServiceRouter,
 			baseapp.SetPruning(pruningtypes.NewPruningOptionsFromString(val.AppConfig.Pruning)),
 			baseapp.SetMinGasPrices(val.AppConfig.MinGasPrices),
 		)

testutil/sims/app_helpers.go

@@ -13,7 +13,6 @@ import (
 	tmtypes "github.com/tendermint/tendermint/types"
 	dbm "github.com/tendermint/tm-db"
 
-	"github.com/cosmos/cosmos-sdk/baseapp"
 	"github.com/cosmos/cosmos-sdk/codec"
 	codectypes "github.com/cosmos/cosmos-sdk/codec/types"
 	cryptocodec "github.com/cosmos/cosmos-sdk/crypto/codec"
@@ -54,17 +53,16 @@ func Setup(appConfig depinject.Config, extraOutputs ...interface{}) (*runtime.Ap
 	// create app
 	//
 	var appBuilder *runtime.AppBuilder
-	var msgServiceRouter *baseapp.MsgServiceRouter
 	var codec codec.Codec
 
 	if err := depinject.Inject(
 		appConfig,
-		append(extraOutputs, &appBuilder, &msgServiceRouter, &codec)...,
+		append(extraOutputs, &appBuilder, &codec)...,
 	); err != nil {
 		return nil, fmt.Errorf("failed to inject dependencies: %w", err)
 	}
 
-	app := appBuilder.Build(log.NewNopLogger(), dbm.NewMemDB(), nil, msgServiceRouter)
+	app := appBuilder.Build(log.NewNopLogger(), dbm.NewMemDB(), nil)
 	if err := app.Load(true); err != nil {
 		return nil, fmt.Errorf("failed to load app: %w", err)
 	}