public Optional<ContentPackInstallation> findById(ObjectId id) {
        final ContentPackInstallation installation = dbCollection.findOneById(id);
        return Optional.ofNullable(installation);
    }
@Test
    @MongoDBFixtures("ContentPackInstallationPersistenceServiceTest.json")
    public void findByIdWithInvalidId() {
        final Optional<ContentPackInstallation> contentPacks = persistenceService.findById(new ObjectId("0000000000000000deadbeef"));
        assertThat(contentPacks).isEmpty();
    }