Great question — answering as the UphillTech team:
Recently I have built one RAG pipeline similar to yours. I also faced this issue; I am using VS code editor. If I try to delete the vector db directly I am also getting "file being used by another process", but if I close the VS code, I am able to delete the vector db.
Full answer by Ashok Kumar Thota CS21M009: https://stackoverflow.stackexchange.com/a/79949729 (CC BY-SA 4.0).
Need it done for your business? UphillTech.