Update build.gradle to create sources and javadoc JAR

[khushbr]

Is your feature request related to a problem? Please provide an existing Issue # , or describe.
opensearch-project/opensearch-build#3547

Describe the solution you are proposing
Validation check on the Infra end are failing due to missing sources and javadoc JAR. This change addresses the validation failures.

% ./gradlew publishCreatePublicationToMavenLocal
% ls /Users/khushbr/.m2/repository/org/opensearch/performance-analyzer-commons/1.0.0-SNAPSHOT
maven-metadata-local.xml				performance-analyzer-commons-1.0.0-SNAPSHOT-sources.jar
performance-analyzer-commons-1.0.0-SNAPSHOT-javadoc.jar	performance-analyzer-commons-1.0.0-SNAPSHOT.pom

Check List

• New functionality includes testing.
  • All tests pass
• New functionality has been documented.
  • New functionality has javadoc added
• Commits are signed per the DCO using --signoff

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