feat(runtime): Add missing NewTransientStoreService (backport #20261) (#20327)

Co-authored-by: beer-1 <147697694+beer-1@users.noreply.github.com>

runtime/store.go

@@ -32,6 +32,10 @@ func (m memStoreService) OpenMemoryStore(ctx context.Context) store.KVStore {
 	return newKVStore(sdk.UnwrapSDKContext(ctx).KVStore(m.key))
 }
 
+func NewTransientStoreService(storeKey *storetypes.TransientStoreKey) store.TransientStoreService {
+	return &transientStoreService{key: storeKey}
+}
+
 type transientStoreService struct {
 	key *storetypes.TransientStoreKey
 }