Update mkdocstrings[python] requirement in the dependencies group (#517)

Updates the requirements on [mkdocstrings[python]](https://github.com/mkdocstrings/mkdocstrings) to permit the latest version.

Updates `mkdocstrings[python]` to 0.26.0
- [Release notes](https://github.com/mkdocstrings/mkdocstrings/releases)
- [Changelog](https://github.com/mkdocstrings/mkdocstrings/blob/main/CHANGELOG.md)
- [Commits](mkdocstrings/mkdocstrings@0.25.0...0.26.0)

---
updated-dependencies:
- dependency-name: mkdocstrings[python]
  dependency-type: direct:production
  dependency-group: dependencies
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

pyproject.toml

@@ -39,7 +39,7 @@ docs = [
     "mkdocs>=1.5.3,<1.7",
     "mkdocs-awesome-pages-plugin~=2.9",
     "mkdocs-material>=9.5.5,<10",
-    "mkdocstrings[python]~=0.25.0",
+    "mkdocstrings[python]~=0.26.0",
 ]
 dev = [
     "mongomock_motor~=0.0.29",