Upgrade to Elasticsearch 7.17.9.

Original Pull Request #2457
Closes #2453

Author: sothawo

pom.xml

@@ -19,9 +19,9 @@
 
 	<properties>
 		<!-- version of the RestHighLevelClient	-->
-		<elasticsearch-rhlc>7.17.8</elasticsearch-rhlc>
+		<elasticsearch-rhlc>7.17.9</elasticsearch-rhlc>
 		<!-- version of the new ElasticsearchClient	-->
-		<elasticsearch-java>7.17.8</elasticsearch-java>
+		<elasticsearch-java>7.17.9</elasticsearch-java>
 		<log4j>2.17.1</log4j>
 		<netty>4.1.65.Final</netty>
 		<springdata.commons>2.7.8-SNAPSHOT</springdata.commons>

src/main/asciidoc/preface.adoc

@@ -37,7 +37,7 @@ built and tested.
 [cols="^,^,^,^,^",options="header"]
 |===
 | Spring Data Release Train | Spring Data Elasticsearch | Elasticsearch | Spring Framework | Spring Boot
-| 2021.2 (Raj) | 4.4.x | 7.17.8 | 5.3.x | 2.7.x
+| 2021.2 (Raj) | 4.4.x | 7.17.9 | 5.3.x | 2.7.x
 | 2021.1 (Q) | 4.3.x | 7.15.2 | 5.3.x | 2.6.x
 | 2021.0 (Pascal) | 4.2.xfootnote:oom[Out of maintenance] | 7.12.0 | 5.3.x | 2.5.x
 | 2020.0 (Ockham)footnote:oom[] | 4.1.xfootnote:oom[] | 7.9.3 | 5.3.2 | 2.4.x

src/main/asciidoc/reference/elasticsearch-migration-guide-4.3-4.4.adoc

@@ -82,7 +82,7 @@ The dependencies for the new Elasticsearch client are still optional in Spring D
     <dependency>
         <groupId>co.elastic.clients</groupId>
         <artifactId>elasticsearch-java</artifactId>
-        <version>7.17.8</version>
+        <version>7.17.9</version>
         <exclusions>
             <exclusion>
                 <groupId>commons-logging</groupId>
@@ -93,7 +93,7 @@ The dependencies for the new Elasticsearch client are still optional in Spring D
     <dependency>
         <groupId>org.elasticsearch.client</groupId>
         <artifactId>elasticsearch-rest-client</artifactId> <!-- is Apache 2-->
-        <version>7.17.8</version>
+        <version>7.17.9</version>
         <exclusions>
             <exclusion>
                 <groupId>commons-logging</groupId>

src/test/resources/testcontainers-elasticsearch.properties

@@ -15,7 +15,7 @@
 #
 #
 sde.testcontainers.image-name=docker.elastic.co/elasticsearch/elasticsearch
-sde.testcontainers.image-version=7.17.8
+sde.testcontainers.image-version=7.17.9
 #
 #
 # needed as we do a DELETE /* at the end of the tests, will be required from 8.0 on, produces a warning since 7.13