Fix SonarCube finding.

Author: phipag

powertools-logging/powertools-logging-logback/src/test/java/software/amazon/lambda/powertools/logging/internal/LambdaJsonEncoderTest.java

@@ -217,9 +217,9 @@ void shouldLogStructuredArgumentsAsNewEntries() {
         StructuredArgument argument = StructuredArguments.entry("msg", msg);
 
         // WHEN
-        LoggingEvent loggingEvent = new LoggingEvent("fqcn", logger, Level.INFO, "A message", null,
+        LoggingEvent structuredLoggingEvent = new LoggingEvent("fqcn", logger, Level.INFO, "A message", null,
                 new Object[] { argument });
-        byte[] encoded = encoder.encode(loggingEvent);
+        byte[] encoded = encoder.encode(structuredLoggingEvent);
         String result = new String(encoded, StandardCharsets.UTF_8);
 
         // THEN (logged as JSON)