Bump Selenium.WebDriver from 4.20.0 to 4.21.0 (#325)

Bumps [Selenium.WebDriver](https://github.com/SeleniumHQ/selenium) from 4.20.0 to 4.21.0.
- [Release notes](https://github.com/SeleniumHQ/selenium/releases)
- [Commits](SeleniumHQ/selenium@selenium-4.20.0...selenium-4.21.0)

---
updated-dependencies:
- dependency-name: Selenium.WebDriver
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

WebDriverManager.Tests/WebDriverManager.Tests.csproj

@@ -10,7 +10,7 @@
         <PackageReference Include="coverlet.msbuild" Version="6.0.2" />
         <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.9.0" />
         <PackageReference Include="xunit.runner.visualstudio" Version="2.8.0" />
-        <PackageReference Include="Selenium.WebDriver" Version="4.20.0" />
+        <PackageReference Include="Selenium.WebDriver" Version="4.21.0" />
         <PackageReference Include="xunit" Version="2.8.0" />
     </ItemGroup>