Bump gdown from 5.2.0 to 5.2.1

Bumps [gdown](https://github.com/wkentaro/gdown) from 5.2.0 to 5.2.1.
- [Release notes](https://github.com/wkentaro/gdown/releases)
- [Commits](wkentaro/gdown@v5.2.0...v5.2.1)

---
updated-dependencies:
- dependency-name: gdown
  dependency-version: 5.2.1
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

pyproject.toml

@@ -49,7 +49,7 @@ test = ["pytest",
         "phantominator",
         "testfixtures==8.3.0",
         "requests==2.33.0"]
-example = ["gdown==5.2.0"]
+example = ["gdown==5.2.1"]
 docs = [ "sphinx-mdinclude==0.6.2",
     "sphinx-copybutton==0.5.2",
     "sphinx-tabs==3.4.7",