[ML] [Inference] fix number inference models returned in x-pack info call (#53540) (#53560)

the ML portion of the x-pack info API was erroneously counting configuration documents and definition documents. The underlying implementation of our storage separates the two out.

This PR filters the query so that only trained model config documents are counted.

Author: benwtrent

x-pack/plugin/ml/src/main/java/org/elasticsearch/xpack/ml/MachineLearningFeatureSet.java

@@ -24,6 +24,7 @@
 import org.elasticsearch.common.Nullable;
 import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.env.Environment;
+import org.elasticsearch.index.query.QueryBuilders;
 import org.elasticsearch.ingest.IngestStats;
 import org.elasticsearch.license.XPackLicenseState;
 import org.elasticsearch.plugins.Platforms;
@@ -39,6 +40,7 @@
 import org.elasticsearch.xpack.core.ml.action.GetJobsStatsAction;
 import org.elasticsearch.xpack.core.ml.datafeed.DatafeedState;
 import org.elasticsearch.xpack.core.ml.dataframe.DataFrameAnalyticsState;
+import org.elasticsearch.xpack.core.ml.inference.TrainedModelConfig;
 import org.elasticsearch.xpack.core.ml.inference.persistence.InferenceIndexConstants;
 import org.elasticsearch.xpack.core.ml.job.config.Job;
 import org.elasticsearch.xpack.core.ml.job.config.JobState;
@@ -351,6 +353,8 @@ public void execute(ActionListener<Usage> listener) {
                     addInferenceIngestUsage(response, inferenceUsage);
                     SearchRequestBuilder requestBuilder = client.prepareSearch(InferenceIndexConstants.INDEX_PATTERN)
                         .setSize(0)
+                        .setQuery(QueryBuilders.boolQuery()
+                            .filter(QueryBuilders.termQuery(InferenceIndexConstants.DOC_TYPE.getPreferredName(), TrainedModelConfig.NAME)))
                         .setTrackTotalHits(true);
                     ClientHelper.executeAsyncWithOrigin(client.threadPool().getThreadContext(),
                         ClientHelper.ML_ORIGIN,