Fix IndicesBoost error.

Original Pull Request #2606
Closes #2598

(cherry picked from commit d9fd722)

Author: sothawo

src/main/java/org/springframework/data/elasticsearch/client/elc/RequestConverter.java

@@ -1246,11 +1246,9 @@ public MsearchRequest searchMsearchRequest(
 							}
 
 							if (!isEmpty(query.getIndicesBoost())) {
-								Map<String, Double> boosts = new LinkedHashMap<>();
-								query.getIndicesBoost()
-										.forEach(indexBoost -> boosts.put(indexBoost.getIndexName(), (double) indexBoost.getBoost()));
-								// noinspection unchecked
-								bb.indicesBoost(boosts);
+								bb.indicesBoost(query.getIndicesBoost().stream()
+										.map(indexBoost -> Map.of(indexBoost.getIndexName(), Double.valueOf(indexBoost.getBoost())))
+										.collect(Collectors.toList()));
 							}
 
 							query.getScriptedFields().forEach(scriptedField -> bb.scriptFields(scriptedField.getFieldName(),
@@ -1412,11 +1410,9 @@ private <T> void prepareSearchRequest(Query query, @Nullable String routing, @Nu
 		}
 
 		if (!isEmpty(query.getIndicesBoost())) {
-			Map<String, Double> boosts = new LinkedHashMap<>();
-			query.getIndicesBoost()
-					.forEach(indexBoost -> boosts.put(indexBoost.getIndexName(), (double) indexBoost.getBoost()));
-			// noinspection unchecked
-			builder.indicesBoost(boosts);
+			builder.indicesBoost(query.getIndicesBoost().stream()
+					.map(indexBoost -> Map.of(indexBoost.getIndexName(), Double.valueOf(indexBoost.getBoost())))
+					.collect(Collectors.toList()));
 		}
 
 		if (!isEmpty(query.getDocValueFields())) {