Bump HtmlSanitizer from 7.1.488 to 7.1.509 (#830)

Bumps [HtmlSanitizer](https://github.com/mganss/HtmlSanitizer) from 7.1.488 to 7.1.509.
- [Release notes](https://github.com/mganss/HtmlSanitizer/releases)
- [Commits](https://github.com/mganss/HtmlSanitizer/compare/v7.1.488...v7.1.509)

---
updated-dependencies:
- dependency-name: HtmlSanitizer
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

ErsatzTV/ErsatzTV.csproj

@@ -57,7 +57,7 @@
       <PackageReference Include="Bugsnag.AspNet.Core" Version="3.0.1" />
       <PackageReference Include="FluentValidation" Version="11.0.2" />
       <PackageReference Include="FluentValidation.AspNetCore" Version="11.0.2" />
-      <PackageReference Include="HtmlSanitizer" Version="7.1.488" />
+      <PackageReference Include="HtmlSanitizer" Version="7.1.509" />
       <PackageReference Include="LanguageExt.Core" Version="4.1.1" />
       <PackageReference Include="Markdig" Version="0.30.2" />
       <PackageReference Include="MediatR.Courier.DependencyInjection" Version="5.0.0" />