Fixed iOS warnings for remote config (#113)

Author: ijunaid

ios/Classes/CountlyiOS/CountlyConfig.h

@@ -105,9 +105,9 @@ extern CLYRequestResult const CLYResponseNetworkIssue;
 extern CLYRequestResult const CLYResponseSuccess;
 extern CLYRequestResult const CLYResponseError;
 
-typedef void (^RCVariantCallback)(CLYRequestResult response, NSError * error);
+typedef void (^RCVariantCallback)(CLYRequestResult response, NSError *_Nullable error);
 
-typedef void (^RCDownloadCallback)(CLYRequestResult response, NSError * error, BOOL fullValueUpdate, NSDictionary<NSString *, CountlyRCData *>* downloadedValues);
+typedef void (^RCDownloadCallback)(CLYRequestResult response, NSError *_Nullable error, BOOL fullValueUpdate, NSDictionary<NSString *, CountlyRCData *>* downloadedValues);
 
 //NOTE: Internal log levels
 typedef enum : NSUInteger

ios/Classes/CountlyiOS/CountlyRemoteConfigInternal.m

@@ -465,7 +465,6 @@ - (void)testingDownloadAllVariantsInternal:(void (^)(CLYRequestResult response,
                     else {
                         [valuesArray addObject:arrayValue];
                     }
-                    printf("%s", valueType);
                 }];
                 variants[key] = valuesArray;
             }];