deps: update dependency cachetools to v5 (#309)

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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/) |

---

### Release Notes

<details>
<summary>tkem/cachetools</summary>

### [`v5.2.0`](https://github.com/tkem/cachetools/blob/HEAD/CHANGELOG.rst#v520-2022-05-29)

[Compare Source](https://github.com/tkem/cachetools/compare/v5.1.0...v5.2.0)

\===================

-   Add `cachetools.keys.methodkey()`.

-   Add `cache_clear()` function to decorators.

-   Add `src` directory to `sys.path` for Sphinx autodoc.

-   Modernize `func` wrappers.

### [`v5.1.0`](https://github.com/tkem/cachetools/blob/HEAD/CHANGELOG.rst#v510-2022-05-15)

[Compare Source](https://github.com/tkem/cachetools/compare/v5.0.0...v5.1.0)

\===================

-   Add cache decorator parameters as wrapper function attributes.

### [`v5.0.0`](https://github.com/tkem/cachetools/blob/HEAD/CHANGELOG.rst#v500-2021-12-21)

[Compare Source](https://github.com/tkem/cachetools/compare/v4.2.4...v5.0.0)

\===================

-   Require Python 3.7 or later (breaking change).

-   Remove deprecated submodules (breaking change).

    The `cache`, `fifo`, `lfu`, `lru`, `mru`, `rr` and
    `ttl` submodules have been deleted.  Therefore, statements like

    `from cachetools.ttl import TTLCache`

    will no longer work. Use

    `from cachetools import TTLCache`

    instead.

-   Pass `self` to `@cachedmethod` key function (breaking change).

    The `key` function passed to the `@cachedmethod` decorator is
    now called as `key(self, *args, **kwargs)`.

    The default key function has been changed to ignore its first
    argument, so this should only affect applications using custom key
    functions with the `@cachedmethod` decorator.

-   Change exact time of expiration in `TTLCache` (breaking change).

    `TTLCache` items now get expired if their expiration time is less
    than *or equal to* `timer()`.  For applications using the default
    `timer()`, this should be barely noticable, but it may affect the
    use of custom timers with larger tick intervals.  Note that this
    also implies that a `TTLCache` with `ttl=0` can no longer hold
    any items, since they will expire immediately.

-   Change `Cache.__repr__()` format (breaking change).

    String representations of cache instances now use a more compact and
    efficient format, e.g.

    `LRUCache({1: 1, 2: 2}, maxsize=10, currsize=2)`

-   Add TLRU cache implementation.

-   Documentation improvements.

</details>

---

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