fix(cfn): Return RUNNING if an error occurred (#3210)

* fix(cfn): Return RUNNING if an error occurred

Force cache refreshing was a retryable task. However, it didn't return
RUNNING whenever the cache refresh failed, and thus the task failed
immediately. This patch makes the task return RUNNING whenever there's
an exception refreshing the cache so it actually retries.

orca-clouddriver/src/main/groovy/com/netflix/spinnaker/orca/clouddriver/tasks/providers/aws/cloudformation/CloudFormationForceCacheRefreshTask.java

@@ -28,6 +28,7 @@
 import javax.annotation.Nonnull;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Component;
+import retrofit.RetrofitError;
 
 @Component
 public class CloudFormationForceCacheRefreshTask extends AbstractCloudProviderAwareTask
@@ -60,8 +61,11 @@ public TaskResult execute(@Nonnull Stage stage) {
       data.put("stackName", stackName);
     }
 
-    cacheService.forceCacheUpdate(cloudProvider, REFRESH_TYPE, data);
-
+    try {
+      cacheService.forceCacheUpdate(cloudProvider, REFRESH_TYPE, data);
+    } catch (RetrofitError e) {
+      return TaskResult.RUNNING;
+    }
     return TaskResult.SUCCEEDED;
   }