chore(deps): bump Umbraco.Cms, Umbraco.Cms.Infrastructure, Umbraco.Cms.Core and Umbraco.Cms.Web.BackOffice

Bumps [Umbraco.Cms](https://github.com/umbraco/Umbraco-CMS), Umbraco.Cms.Infrastructure, Umbraco.Cms.Core and Umbraco.Cms.Web.BackOffice. These dependencies needed to be updated together.

Updates `Umbraco.Cms` from 10.4.0 to 10.8.5
- [Release notes](https://github.com/umbraco/Umbraco-CMS/releases)
- [Commits](umbraco/Umbraco-CMS@release-10.4.0...release-10.8.5)

Updates `Umbraco.Cms.Infrastructure` from 10.4.0 to 10.8.5

Updates `Umbraco.Cms.Core` from 10.4.0 to 10.8.5

Updates `Umbraco.Cms.Web.BackOffice` from 10.4.0 to 10.8.5

---
updated-dependencies:
- dependency-name: Umbraco.Cms
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: Umbraco.Cms.Infrastructure
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: Umbraco.Cms.Core
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: Umbraco.Cms.Web.BackOffice
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

src/TestSite.10/TestSite.10.csproj

@@ -7,7 +7,7 @@
     </PropertyGroup>
 
     <ItemGroup>
-        <PackageReference Include="Umbraco.Cms" Version="10.4.0"/>
+        <PackageReference Include="Umbraco.Cms" Version="10.8.5"/>
         <PackageReference Include="uSync" Version="10.7.1"/>
     </ItemGroup>