Use the TYPE constant for the name here

This makes this class more like SnapshotLifecycleMetadata and
IndexLifecycleMetadata, but I don't think this is load bearing code.
The previous String literal version was more like EnrichMetadata, so
there's prior art for that, but it feels more like an odd duck to me.

Author: joegallo

modules/ingest-geoip/src/main/java/org/elasticsearch/ingest/geoip/IngestGeoIpMetadata.java

@@ -46,7 +46,7 @@ public final class IngestGeoIpMetadata implements Metadata.Custom {
 
     @SuppressWarnings("unchecked")
     private static final ConstructingObjectParser<IngestGeoIpMetadata, Void> PARSER = new ConstructingObjectParser<>(
-        "ingest_geoip_metadata",
+        TYPE,
         a -> new IngestGeoIpMetadata(
             ((List<DatabaseConfigurationMetadata>) a[0]).stream().collect(Collectors.toMap((m) -> m.database().id(), Function.identity()))
         )