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[Damian19866]

Changes

Checks file cache for expired items at the end of a run.

Context

Closes #13732

Documentation (please check one with an [x])

• [x] I have updated the documentation, or
• [x] No documentation update is required

How I've tested my work (please select one)

I have verified these changes via:

• [x] Code inspection only, or
• [ ] Newly added/modified unit tests, or
• [x] No unit tests but ran on a real repository, or
• [ ] Both unit tests + ran on a real repository

Originally posted by @rarkins in https://github.com/renovatebot/renovate/pull/20061