At present, the `neo4jObservationCustomizer` has an effective `Ordered.LOWEST_PRECEDENCE`, meaning that it goes last in `Neo4jAutoConfiguration`:
```java
configBuilderCustomizers.orderedStream().toList()
...
customizers.forEach((customizer) -> customizer.customize(builder));
```

This update sets its order to `Ordered.HIGHEST_PRECEDENCE`, meaning that a user-defined `ConfigBuilderCustomizer` can effectively override it.

As an example, this is useful when user wants to customize `MicrometerObservationProvider` as it actually has some optional properties that may be useful. Here is an example:
```java
@bean
ConfigBuilderCustomizer observationCustomizer(ObservationRegistry observationRegistry) {
    return configBuilder -> {
        var observationProvider = MicrometerObservationProvider.builder(observationRegistry)
                .alwaysIncludeQuery(true)
                .includeQueryParameters(true)
                .includeUrlScheme(true)
                .includeUrlTemplate(true)
                .requestHeaderPredicate(name -> true)
                .responseHeaderPredicate(name -> true)
                .build();
        configBuilder.withObservationProvider(observationProvider);
    };
}
```

Signed-off-by: Dmitriy Tverdiakov <[email protected]>