UnsuccessfulResponseException: 500 when syncing with wallabag.it

Description: Cannot sync android app with wallabag.it. Results in `UnsuccessfulResponseException: HTTP response: 500 `

Steps to reproduce:
1. Open android app
2. Manually refresh

Alternative steps:
1. Share a link from another app to the wallabag app
2. The popup with the Star, Mark as Read, Tag and Open buttons appears
3. Pressing the Open button leads to the error and it never loads

App details:
- Android app version: 2.5.3 (f-droid)
- Android 16, stock
- Google Pixel 6a

Server:
- I'm using the wallabag.it instance (in other words, i am not self-hosting so have no control over the configuration)

Additional details:
- I have no errors when using the same sever with the same account from the website or the browser extension
- This looks like a repeat of #1247 which didn't lead to an answer
- I have not yet tried deleting the app's data or reinstalling it

# Stack trace
```
Server error
wallabag.apiwrapper.exceptions.UnsuccessfulResponseException: HTTP response: 500
Stacktrace:
wallabag.apiwrapper.exceptions.UnsuccessfulResponseException: HTTP response: 500
at wallabag.apiwrapper.WallabagService.checkResponse(WallabagService.java:1525)
at wallabag.apiwrapper.WallabagService.checkResponseBody(WallabagService.java:1503)
at wallabag.apiwrapper.WallabagService.execAndCheckBody(WallabagService.java:1499)
at wallabag.apiwrapper.WallabagService.lambda$modifyArticle$7$wallabag-apiwrapper-WallabagService(WallabagService.java:868)
at wallabag.apiwrapper.WallabagService$$ExternalSyntheticLambda4.run(D8$$SyntheticClass:0)
at wallabag.apiwrapper.NotFoundPolicy.call(NotFoundPolicy.java:140)
at wallabag.apiwrapper.NotFoundPolicy.call(NotFoundPolicy.java:133)
at wallabag.apiwrapper.NotFoundPolicy.call(NotFoundPolicy.java:128)
at wallabag.apiwrapper.WallabagService.modifyArticle(WallabagService.java:868)
at wallabag.apiwrapper.ModifyArticleBuilder.execute(ModifyArticleBuilder.java:103)
at wallabag.apiwrapper.ModifyArticleBuilder.execute(ModifyArticleBuilder.java:86)
at fr.gaulupeau.apps.Poche.service.workers.OfflineChangesSynchronizer.syncArticleChange(OfflineChangesSynchronizer.java:368)
at fr.gaulupeau.apps.Poche.service.workers.OfflineChangesSynchronizer.syncOfflineQueue(OfflineChangesSynchronizer.java:118)
at fr.gaulupeau.apps.Poche.service.workers.OfflineChangesSynchronizer.synchronize(OfflineChangesSynchronizer.java:68)
at fr.gaulupeau.apps.Poche.service.tasks.SyncOfflineChangesTask.run(SyncOfflineChangesTask.java:17)
at fr.gaulupeau.apps.Poche.service.tasks.ActionRequestTask.run(ActionRequestTask.java:25)
at fr.gaulupeau.apps.Poche.service.TaskService$$ExternalSyntheticLambda2.run(D8$$SyntheticClass:0)
at fr.gaulupeau.apps.Poche.service.TaskService.run(TaskService.java:162)
at fr.gaulupeau.apps.Poche.service.TaskService.$r8$lambda$7B6NdHPPL8YMNadJyfVPhGC-s2M(Unknown Source:0)
at fr.gaulupeau.apps.Poche.service.TaskService$$ExternalSyntheticLambda1.run(D8$$SyntheticClass:0)
at java.lang.Thread.run(Thread.java:1119)

```