Doc: Incorrect API referenced in metrics doc

[slto]

Environment Details

• Helidon Version: 2.0.1
• Helidon SE
• JDK version: 11.0.8
• OS: Linux
• Docker version (if applicable):

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Problem Description

The 2.0 metrics documentation on helidon.io site seems incorrect
https://helidon.io/docs/v2/#/se/metrics/01_metrics

It is referencing APIs that don't exists in Helidon 2.0
import io.helidon.metrics.RegistryFactory;
...
private final MetricRegistry registry = RegistryFactory.getRegistryFactory().get()
.getRegistry(MetricRegistry.Type.APPLICATION);

The Helidon SE Metrics Guide uses the correct API
https://helidon.io/docs/v2/#/se/guides/05_metrics

RegistryFactory metricsRegistry = RegistryFactory.getInstance();
MetricRegistry appRegistry = metricsRegistry.getRegistry(MetricRegistry.Type.APPLICATION);

Steps to reproduce