chore: fix error in samples

Author: Davide Melfi

samples/kinesis-firehose-event-handler/pom.xml

@@ -52,7 +52,7 @@
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter</artifactId>
-            <version>RELEASE</version>
+            <version>5.9.2</version>
             <scope>test</scope>
         </dependency>
         <dependency>