Bump elasticsearch from 2.4.3 to 6.8.13

Bumps [elasticsearch](https://github.com/elastic/elasticsearch) from 2.4.3 to 6.8.13.
- [Release notes](https://github.com/elastic/elasticsearch/releases)
- [Commits](elastic/elasticsearch@v2.4.3...v6.8.13)

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

pom.xml

@@ -171,7 +171,7 @@
                 <dependency>
                     <groupId>org.elasticsearch</groupId>
                     <artifactId>elasticsearch</artifactId>
-                    <version>2.4.3</version>
+                    <version>6.8.13</version>
                     <scope>provided</scope>
                 </dependency>
             </dependencies>
@@ -185,7 +185,7 @@
                 <dependency>
                     <groupId>org.elasticsearch</groupId>
                     <artifactId>elasticsearch</artifactId>
-                    <version>5.6.16</version>
+                    <version>6.8.13</version>
                     <scope>provided</scope>
                 </dependency>
                 <dependency>
@@ -217,7 +217,7 @@
                 <dependency>
                     <groupId>org.elasticsearch</groupId>
                     <artifactId>elasticsearch</artifactId>
-                    <version>6.0.1</version>
+                    <version>6.8.13</version>
                     <scope>provided</scope>
                 </dependency>
                 <dependency>
@@ -249,7 +249,7 @@
                 <dependency>
                     <groupId>org.elasticsearch</groupId>
                     <artifactId>elasticsearch</artifactId>
-                    <version>6.8.10</version>
+                    <version>6.8.13</version>
                     <scope>provided</scope>
                 </dependency>
                 <dependency>
@@ -281,7 +281,7 @@
                 <dependency>
                     <groupId>org.elasticsearch</groupId>
                     <artifactId>elasticsearch</artifactId>
-                    <version>7.9.0</version>
+                    <version>6.8.13</version>
                     <scope>provided</scope>
                 </dependency>
                 <dependency>