Update dependency pip to v25 (#372)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [pip](https://redirect.github.com/pypa/pip)
([changelog](https://pip.pypa.io/en/stable/news/)) | `24.3.1` ->
`25.0.1` |
[![age](https://developer.mend.io/api/mc/badges/age/pypi/pip/25.0.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/pypi/pip/25.0.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/pypi/pip/24.3.1/25.0.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/pypi/pip/24.3.1/25.0.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

<details>
<summary>pypa/pip (pip)</summary>

###
[`v25.0.1`](https://redirect.github.com/pypa/pip/compare/25.0...25.0.1)

[Compare
Source](https://redirect.github.com/pypa/pip/compare/25.0...25.0.1)

###
[`v25.0`](https://redirect.github.com/pypa/pip/compare/24.3.1...25.0)

[Compare
Source](https://redirect.github.com/pypa/pip/compare/24.3.1...25.0)

</details>

---

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charmcraft.yaml

@@ -24,7 +24,7 @@ parts:
       # Use environment variable instead of `--break-system-packages` to avoid failing on older
       # versions of pip that do not recognize `--break-system-packages`
       # `--user` needed (in addition to `--break-system-packages`) for Ubuntu >=24.04
-      PIP_BREAK_SYSTEM_PACKAGES=true python3 -m pip install --user --upgrade pip==24.3.1  # renovate: charmcraft-pip-latest
+      PIP_BREAK_SYSTEM_PACKAGES=true python3 -m pip install --user --upgrade pip==25.0.1  # renovate: charmcraft-pip-latest
 
       # Use uv to install poetry so that a newer version of Python can be installed if needed by poetry
       curl --proto '=https' --tlsv1.2 -LsSf https://github.com/astral-sh/uv/releases/download/0.5.20/uv-installer.sh | sh  # renovate: charmcraft-uv-latest