### Description

I was just looking at some Elasticsearch that had lots of "Improve "reloading search analyzers" logs coming from `MapperService` at the INFO level. In my particular case, it was being emitted because analyzers are reloaded as part of doing a recovery. This log is not really helpful as-is, I think we need to do the following:
 - Switch the level to DEBUG, it's not important enough to warrant an INFO log.
 - Add which index reloaded its search analyzers to the log.

What do you think?
server/src/main/java/org/elasticsearch/index/mapper/MapperService.java
super(indexSettings);
        this.indexVersionCreated = indexSettings.getIndexVersionCreated();
        this.indexAnalyzers = indexAnalyzers;
        this.mapperRegistry = mapperRegistry;
        this.mappingParserContextSupplier = () -> new MappingParserContext(
            similarityService::getSimilarity,
            type -> mapperRegistry.getMapperParser(type, indexVersionCreated),
            mapperRegistry.getRuntimeFieldParsers()::get,
            indexVersionCreated,
            clusterTransportVersion,
            searchExecutionContextSupplier,
            scriptCompiler,
            indexAnalyzers,
            indexSettings,
            idFieldMapper
        );
        this.documentParser = new DocumentParser(
            parserConfiguration,
            this.mappingParserContextSupplier.get(),
            documentParsingObserverSupplier
        );
        Map<String, MetadataFieldMapper.TypeParser> metadataMapperParsers = mapperRegistry.getMetadataMapperParsers(
            indexSettings.getIndexVersionCreated()
        );
        this.mappingParser = new MappingParser(
            mappingParserContextSupplier,
            metadataMapperParsers,
            this::getMetadataMappers,
            this::resolveDocumentType
        );