deps: update dependency cachetools to v5 (#716)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [cachetools](https://github.com/tkem/cachetools) | `==4.2.4` -> `==5.2.0` | [![age](https://badges.renovateapi.com/packages/pypi/cachetools/5.2.0/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/pypi/cachetools/5.2.0/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/pypi/cachetools/5.2.0/compatibility-slim/4.2.4)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/pypi/cachetools/5.2.0/confidence-slim/4.2.4)](https://docs.renovatebot.com/merge-confidence/) |

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