fix: download files with relative url (#1216)

* hard fix

* test

* Revert "test"

This reverts commit 1fe9247.

* error handler

[URL](https://github.com/facebook/react-native/blob/v0.72.10/packages/react-native/Libraries/Blob/URL.js)

src/services/download/downloadChapter.ts

@@ -49,7 +49,8 @@ const downloadFiles = async (
       const fileurl = `${folder}/${i}.b64.png`;
       elem.attr('src', `file://${fileurl}`);
       try {
-        await downloadFile(url, fileurl, plugin.imageRequestInit);
+        const absoluteURL = new URL(url, plugin.site).href;
+        await downloadFile(absoluteURL, fileurl, plugin.imageRequestInit);
       } catch (e) {
         elem.attr('alt', String(e));
       }