Review fixes for okhttp-2.2:javaagent (open-telemetry#17557)

Co-authored-by: otelbot <197425009+otelbot@users.noreply.github.com>

Author: otelbot[bot]

instrumentation/okhttp/okhttp-2.2/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/okhttp/v2_2/OkHttp2Singletons.java

@@ -18,7 +18,7 @@ public final class OkHttp2Singletons {
   private static final String INSTRUMENTATION_NAME = "io.opentelemetry.okhttp-2.2";
 
   private static final Instrumenter<Request, Response> instrumenter;
-  private static final TracingInterceptor TRACING_INTERCEPTOR;
+  private static final TracingInterceptor tracingInterceptor;
 
   public static final VirtualField<Runnable, PropagatedContext> PROPAGATED_CONTEXT =
       VirtualField.find(Runnable.class, PropagatedContext.class);
@@ -28,12 +28,12 @@ public final class OkHttp2Singletons {
         JavaagentHttpClientInstrumenters.create(
             INSTRUMENTATION_NAME, new OkHttp2HttpAttributesGetter());
 
-    TRACING_INTERCEPTOR =
+    tracingInterceptor =
         new TracingInterceptor(instrumenter, GlobalOpenTelemetry.get().getPropagators());
   }
 
   public static Interceptor tracingInterceptor() {
-    return TRACING_INTERCEPTOR;
+    return tracingInterceptor;
   }
 
   private OkHttp2Singletons() {}

instrumentation/okhttp/okhttp-2.2/javaagent/src/main/java/io/opentelemetry/javaagent/instrumentation/okhttp/v2_2/TracingInterceptor.java

@@ -14,7 +14,7 @@
 import io.opentelemetry.instrumentation.api.instrumenter.Instrumenter;
 import java.io.IOException;
 
-public class TracingInterceptor implements Interceptor {
+public final class TracingInterceptor implements Interceptor {
   private final Instrumenter<Request, Response> instrumenter;
   private final ContextPropagators propagators;