[TEST] set back the visibility of our search ext plugin in FetchSubPhasePluginIT to private

This plugin is not used in other tests anymore, it should be private to make sure its usage doesn't spread again

core/src/test/java/org/elasticsearch/search/fetch/FetchSubPhasePluginIT.java

@@ -118,7 +118,7 @@ public class FetchSubPhasePluginIT extends ESIntegTestCase {
         }
     }
 
-    public static final class TermVectorsFetchSubPhase implements FetchSubPhase {
+    private static final class TermVectorsFetchSubPhase implements FetchSubPhase {
         private static final String NAME = "term_vectors_fetch";
 
         @Override
@@ -153,7 +153,7 @@ public class FetchSubPhasePluginIT extends ESIntegTestCase {
         }
     }
 
-    public static final class TermVectorsFetchParser implements SearchExtParser<TermVectorsFetchBuilder> {
+    private static final class TermVectorsFetchParser implements SearchExtParser<TermVectorsFetchBuilder> {
 
         private static final TermVectorsFetchParser INSTANCE = new TermVectorsFetchParser();
 
@@ -176,18 +176,18 @@ public class FetchSubPhasePluginIT extends ESIntegTestCase {
         }
     }
 
-    public static final class TermVectorsFetchBuilder extends SearchExtBuilder {
+    private static final class TermVectorsFetchBuilder extends SearchExtBuilder {
         private final String field;
 
-        public TermVectorsFetchBuilder(String field) {
+        private TermVectorsFetchBuilder(String field) {
             this.field = field;
         }
 
-        public TermVectorsFetchBuilder(StreamInput in) throws IOException {
+        private TermVectorsFetchBuilder(StreamInput in) throws IOException {
             this.field = in.readString();
         }
 
-        public String getField() {
+        private String getField() {
             return field;
         }