Fixing release-only crash for when specifying validKeys[Down|Up] (#1883)

Wrong macro -- use `RCT_ARRAY_CONVERTER`, not `RCT_JSON_ARRAY_CONVERTER`. The latter is for "directly representable json array values that require no conversion.":

`/**
 * This macro is used for creating converter functions for directly
 * representable json array values that require no conversion.
 */
  +(NSArray *)name##Array : (id)json               \
  {                                                \
    return json;                                   \
  }

`/**
 * This macro is used for creating converter functions for typed arrays.
 * RCT_ARRAY_CONVERTER_NAMED may be used when type contains characters
 * which are disallowed in selector names.
 */

Author: nakambo

React/Base/RCTConvert.m

@@ -1502,7 +1502,7 @@ + (NSString *)accessibilityRoleFromTraits:(id)json
   return NSAccessibilityUnknownRole;
 }
 
-RCT_JSON_ARRAY_CONVERTER(RCTHandledKey);
+RCT_ARRAY_CONVERTER(RCTHandledKey);
 
 #endif // macOS]