Use the new-in-Java-19 pre-sized HashMap utility

On Elasticsearch 9.0 and above, the minimum JVM version is 21, so we
can use new-fangled functions like this.

Author: joegallo

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

@@ -266,7 +266,7 @@ protected Map<String, Object> transform(final CityResponse response) {
                         Double latitude = location.getLatitude();
                         Double longitude = location.getLongitude();
                         if (latitude != null && longitude != null) {
-                            Map<String, Object> locationObject = new HashMap<>();
+                            Map<String, Object> locationObject = HashMap.newHashMap(2);
                             locationObject.put("lat", latitude);
                             locationObject.put("lon", longitude);
                             data.put("location", locationObject);
@@ -539,7 +539,7 @@ protected Map<String, Object> transform(final EnterpriseResponse response) {
                         Double latitude = location.getLatitude();
                         Double longitude = location.getLongitude();
                         if (latitude != null && longitude != null) {
-                            Map<String, Object> locationObject = new HashMap<>();
+                            Map<String, Object> locationObject = HashMap.newHashMap(2);
                             locationObject.put("lat", latitude);
                             locationObject.put("lon", longitude);
                             data.put("location", locationObject);