Too many dav UploadCleanup in the job list

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Steps to reproduce

1. Create a lot of 'apps/dav/lib/BackgroundJob/UploadCleanup' jobs (> 50 000)
2. Use https://github.com/nextcloud/server/pull/30359 to run these jobs

Expected behaviour

UploadCleanup jobs are only executed less often when not needed

Actual behaviour

After 14 minutes, the cron job stops and there is little difference in the number of jobs since these jobs are only deleted if the files in the upload directory are older than 24 hours or if the upload finishes.

This is causing issues as the same jobs get processed over and over again, wasting resources and potentially blocking other jobs to run.

Server configuration

Database: mysal

PHP version: 8.0

Nextcloud version: master

Primary storage: s3

Start by inspecting apps/dav/lib/BackgroundJob/UploadCleanup and reproduce the behavior with many jobs, using pull request #30359 as described. Trace why jobs remain in the list and compare the observed scheduling with the expected behavior; done means unnecessary UploadCleanup jobs no longer repeatedly consume cron resources.