Remove unused local variable flagged by CodeQL

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: torosent

samples/src/main/java/io/durabletask/samples/TracingPattern.java

@@ -55,7 +55,7 @@ public static void main(String[] args) throws IOException, InterruptedException,
                 .addSpanProcessor(BatchSpanProcessor.builder(spanExporter).build())
                 .build();
 
-        OpenTelemetrySdk openTelemetry = OpenTelemetrySdk.builder()
+        OpenTelemetrySdk.builder()
                 .setTracerProvider(tracerProvider)
                 .buildAndRegisterGlobal();