fix: remove duplicate junit-version property from pom.xml

Duplicate property removed to fix P2 issue from cubic-dev-ai review.

Author: Chhida

samples/client/petstore/java/jersey3-oneOf/pom.xml

@@ -358,7 +358,6 @@
         <commons-lang3-version>3.12.0</commons-lang3-version>
         <http-signature-version>1.8</http-signature-version>
         <junit-version>5.10.0</junit-version>
-        <junit-version>5.10.0</junit-version>
         <spotless.version>2.21.0</spotless.version>
     </properties>
 </project>