Revert "test retry in case of not retryable"

This reverts commit 83921df.

Author: msk-nkhr

src/main/java/io/digdag/plugin/slack/SlackOperatorFactory.java

@@ -13,12 +13,10 @@
 import okhttp3.Call;
 import okhttp3.FormBody;
 import okhttp3.Interceptor;
-import okhttp3.MediaType;
 import okhttp3.OkHttpClient;
 import okhttp3.Request;
 import okhttp3.RequestBody;
 import okhttp3.Response;
-import okhttp3.ResponseBody;
 
 import java.io.IOException;
 import java.util.Arrays;
@@ -122,8 +120,7 @@ static class RetryInterceptor implements Interceptor
         public Response intercept(Chain chain) throws IOException
         {
             Request request = chain.request();
-            // Response response = chain.proceed(request);
-            Response response = new Response.Builder().code(404).message("not found").body(ResponseBody.create(MediaType.parse("application/json; charset=utf-8"), "{}")).protocol(okhttp3.Protocol.HTTP_1_1).request(request).build();
+            Response response = chain.proceed(request);
             int retryCount = 0;
             while (!response.isSuccessful() && retryCount < MAX_RETRY_COUNT && Arrays.asList(retryHttpStatus).contains(response.code())) {
                 retryCount++;