Fix modular example taking forever

.github/workflows/main.yml

@@ -150,6 +150,7 @@ jobs:
     name: "Integration tests"
     needs: [setup]
     runs-on: ubuntu-latest
+    timeout-minutes: 10
     services:
       postgres:
         image: postgres

examples/modular/bin/example.dart

@@ -9,4 +9,5 @@ void main() async {
 
   await database.myAccessor
       .addUser(user: UsersCompanion.insert(name: 'first_user'));
+  await database.close();
 }