Fix:When deleting a knowledge base that is currently performing a parsing task, the parsing queue will not be deleted! (#9018)
### What problem does this PR solve?
https://github.com/infiniflow/ragflow/issues/8995
### Type of change
- [x] Bug Fix (non-breaking change which fixes an issue)
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Co-authored-by: Kevin Hu <kevinhu.sh@gmail.com>