HSEARCH-4764 Bump auth from 2.18.1 to 2.19.8

Bumps auth from 2.18.1 to 2.19.8.

---
updated-dependencies:
- dependency-name: software.amazon.awssdk:auth
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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pom.xml

@@ -232,7 +232,7 @@
         <version.org.opensearch.latest>2.4.1</version.org.opensearch.latest>
 
         <version.com.google.code.gson>2.9.1</version.com.google.code.gson>
-        <version.software.amazon.awssdk>2.18.1</version.software.amazon.awssdk>
+        <version.software.amazon.awssdk>2.19.8</version.software.amazon.awssdk>
         <!-- Jackson: used by the Elasticsearch REST client, the AWS SDK and in tests (wiremock, ...) -->
         <version.com.fasterxml.jackson>2.13.4</version.com.fasterxml.jackson>
         <!--