in UpdateMapperUnitTests#mapNestedIntegerFieldCorrectly, when change the last integer to grater than 10, like this:
    @Test
    void mapNestedIntegerFieldCorrectly() {
        Update update = new Update().set("levelOne.0.1.32", "4");
        Document mappedUpdate = mapper.getMappedObject(update.getUpdateObject(),
            context.getPersistentEntity(EntityWithNestedMap.class));
        assertThat(mappedUpdate).isEqualTo(new org.bson.Document("$set", new org.bson.Document("levelOne.0.1.32", "4")));
    }
then add a 2rd field in EntityWithNestedMap, like this:
	static class EntityWithNestedMap {
		Map<String, Map<String, Map<String, Object>>> levelOne;
		Map<String, Map<String, Map<String, Object>>> levelOne2;
	}
then, the test fails.
Expected :{"$set"={"levelOne.0.1.32"="4"}}
Actual   :{"$set"={"levelOne2.0"="4"}}