fix(CustomExport): 修复自定义导出进度条错误的问题

app/src/main/res/values/strings.xml

@@ -30,7 +30,7 @@
     <string name="edit">Edit</string>
     <string name="delete">Delete</string>
     <string name="delete_all">Delete all</string>
-    <string name="custom_export_section">Custom export chapter</string>
+    <string name="custom_export_section">Custom export chapter of epub</string>
     <string name="replace">Replace</string>
     <string name="replace_purify">Replacement</string>
     <string name="replace_purify_desc">Configure replacement rules</string>