Quirks v2 unable to specify EntityType.DIAGNOSTIC for write_attr_button

[jeverley]

I'm currently writing a quirk for the Aquara FP1E presence sensor https://github.com/zigpy/zha-device-handlers/issues/3294 and I've observed that specifying EntityType.DIAGNOSTIC as the entity_type for write_attr_button entities results in the error:

Logger: zha.application.discovery
Source: components/zha/__init__.py:151
First occurred: 12:57:58 (1 occurrences)
Last logged: 12:57:58

Device: 54:ef:44:10:00:db:47:bb-Aqara Presence Sensor FP1E has an entity with details: {'cluster_details': (1, 64704, <ClusterType.Server: 0>), 'entity_metadata': WriteAttributeButtonMetadata(entity_platform=<EntityPlatform.BUTTON: 'button'>, entity_type=<EntityType.DIAGNOSTIC: 'diagnostic'>, cluster_id=64704, endpoint_id=1, cluster_type=<ClusterType.Server: 0>, initially_disabled=False, attribute_initialized_from_cache=True, translation_key='restart_device', fallback_name='Restart device', attribute_name='restart_device', attribute_value=0)} that does not have an entity class mapping - unable to create entity

This can be replicated with the following entity definition.

    .write_attr_button(
        OppleCluster.AttributeDefs.restart_device.name,
        0,
        OppleCluster.cluster_id,
        entity_type=EntityType.DIAGNOSTIC,
        translation_key="restart_device",
        fallback_name="Restart device",
    )

Investigating the issue it would appear this is due to a mapping for EntityType.DIAGNOSTIC currently being absent in the zha/application/discovery.py QUIRKS_ENTITY_META_TO_ENTITY_CLASS.

There are currently only button.WriteAttributeButton mappings for STANDARD and CONFIG (the default in zigpy/quirks/v2/init.py for write_attr_button entities).

QUIRKS_ENTITY_META_TO_ENTITY_CLASS = {
    (
        Platform.BUTTON,
        WriteAttributeButtonMetadata,
        EntityType.CONFIG,
    ): button.WriteAttributeButton,
    (
        Platform.BUTTON,
        WriteAttributeButtonMetadata,
        EntityType.STANDARD,
    ): button.WriteAttributeButton,

[dmulcahey]

fixed by #308