Update dependency mypy to v1.12.0 (#378)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [mypy](https://www.mypy-lang.org/)
([source](https://redirect.github.com/python/mypy),
[changelog](https://mypy-lang.blogspot.com/)) | `1.11.2` -> `1.12.0` |
[![age](https://developer.mend.io/api/mc/badges/age/pypi/mypy/1.12.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/pypi/mypy/1.12.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/pypi/mypy/1.11.2/1.12.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/pypi/mypy/1.11.2/1.12.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

<details>
<summary>python/mypy (mypy)</summary>

###
[`v1.12.0`](https://redirect.github.com/python/mypy/compare/v1.11.2...v1.12.0)

[Compare
Source](https://redirect.github.com/python/mypy/compare/v1.11.2...v1.12.0)

</details>

---

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