readMap method
Method for getting a Map with a defined key.
Example:
// RCache.common.readMap(key: RCacheKey("map"));
Implementation
@override
Future<Map<String, dynamic>?> readMap({required RCacheKey key}) async {
  try {
    Map<Object?, Object?>? value = await methodChannel.invokeMethod(
      RCacheMethod.key.read.map,
      rArgs(type: RCacheMethod.key.common, key: key),
    );
    return Future.value(
      value == null ? null : rAutoCastMap(value.cast<String, dynamic>()),
    );
  } on PlatformException catch (e) {
    return Future.error(e);
  }
}