Renovate: dependency cmocean to v4 (#367)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [cmocean](https://togithub.com/matplotlib/cmocean) | `~=3.0` ->
`~=4.0` |
[![age](https://developer.mend.io/api/mc/badges/age/pypi/cmocean/4.0.3?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/pypi/cmocean/4.0.3?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/pypi/cmocean/3.1.3/4.0.3?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/pypi/cmocean/3.1.3/4.0.3?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

<details>
<summary>matplotlib/cmocean (cmocean)</summary>

###
[`v4.0.3`](https://togithub.com/matplotlib/cmocean/releases/tag/v4.0.3)

[Compare
Source](https://togithub.com/matplotlib/cmocean/compare/v4.0.1...v4.0.3)

**Full Changelog**:
matplotlib/cmocean@v4.0.2...v4.0.3

###
[`v4.0.1`](https://togithub.com/matplotlib/cmocean/releases/tag/v4.0.1)

[Compare
Source](https://togithub.com/matplotlib/cmocean/compare/v3.1.3...v4.0.1)

I mess up the initial release every time because I can't remember to
update the version manually. This is the only package I manage where I
have to do that.

</details>

---

### Configuration

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month" (UTC), Automerge - "every weekday" (UTC).

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are satisfied.

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rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update
again.

---

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---

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pyproject.toml

@@ -23,7 +23,7 @@ classifiers = [
     "Typing :: Typed",
 ]
 dependencies = [
-    "cmocean~=3.0",
+    "cmocean~=4.0",
     "gmpy2~=2.0",
     "hypothesis~=6.0",
     "libigl~=2.0",