Clearing multiple bookmarks at a time is inconsistant

[TheIceCreamTroll]

Describe the bug Clearing multiple bookmarked series at a time sometimes fails and sometimes only clears some of selected series. A 400 error is always generated and a page refresh is needed to see the change.

Doesn't seem to matter if they are all comics, all manga, or mixed.

Clearing a single series works as intended.

To Reproduce Steps to reproduce the behavior: 0. Create bookmarks across at least 3 series.

1. Go to the Bookmarks library
2. Select multiple series
3. Click '....' from the top bar. Click "Clear"
4. See "400 Error: Could Not Clear Bookmarks"
5. Reload the page
6. Observe remaining bookmarks

Expected behavior All selected bookmarked series should be cleared, and the WebUI updated without a manual reload.

Desktop (please complete the following information):

• OS: Docker
• Browser Firefox
• Version 0.5.4.14