default boolean isLinkisBMLResources() {
        return true;
    }
ResourceMap is the content of ExportRequestRef exported.
<br>
Now, DSS only supports to import BML resources or one inputStream,
so when you want to use BML resources to import/export, the resourceMap must be
consisted of `resourceId` and `version`; and if you want to use stream to
import/export, the resourceMap must be consisted of `inputStream` and `closeable`.
<br>
The `closeable` is remained field that if your inputStream comes from HttpClient,
you can set the `closeable` to CloseableHttpResponse to void exception.
@return the content of ExportRequestRef exported.
dss-standard/development-standard/development-process-standard/src/main/java/com/webank/wedatasphere/dss/standard/app/development/ref/ImportRequestRef.java