Update types-beautifulsoup4 requirement in /pelican

Updates the requirements on [types-beautifulsoup4](https://github.com/python/typeshed) to permit the latest version.
- [Commits](https://github.com/python/typeshed/commits)

---
updated-dependencies:
- dependency-name: types-beautifulsoup4
  dependency-version: 4.12.0.20250516
  dependency-type: direct:development
...

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Author: dependabot[bot]

pelican/pyproject.toml

@@ -74,7 +74,7 @@ dev = [
     "pylint>=3",
     "types-PyYAML>=6.0",
     "types-requests>=2.33",
-    "types-beautifulsoup4>=4.12",
+    "types-beautifulsoup4>=4.12.0.20250516",
     "types-markdown>=3.10",
 ]