Bump the nuget group with 3 updates

Bumps Umbraco.Cms from 15.4.0 to 15.4.2
Bumps Umbraco.Cms.Core from 15.4.0 to 15.4.2
Bumps Umbraco.Cms.StaticAssets from 15.4.0 to 15.4.2

---
updated-dependencies:
- dependency-name: Umbraco.Cms
  dependency-version: 15.4.2
  dependency-type: direct:production
  dependency-group: nuget
- dependency-name: Umbraco.Cms.Core
  dependency-version: 15.4.2
  dependency-type: direct:production
  dependency-group: nuget
- dependency-name: Umbraco.Cms.StaticAssets
  dependency-version: 15.4.2
  dependency-type: direct:production
  dependency-group: nuget
...

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

Author: dependabot[bot]

src/Umbraco.Cms.15.x/Umbraco.Cms.15.x.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk.Web">
+<Project Sdk="Microsoft.NET.Sdk.Web">
 	<PropertyGroup>
 		<TargetFramework>net9.0</TargetFramework>
 		<ImplicitUsings>enable</ImplicitUsings>
@@ -7,9 +7,9 @@
 	</PropertyGroup>
 
 	<ItemGroup>
-		<PackageReference Include="Umbraco.Cms" Version="15.4.0" />
-		<PackageReference Include="Umbraco.Cms.Core" Version="15.4.0" />
-		<PackageReference Include="Umbraco.Cms.StaticAssets" Version="15.4.0" />
+		<PackageReference Include="Umbraco.Cms" Version="15.4.2" />
+		<PackageReference Include="Umbraco.Cms.Core" Version="15.4.2" />
+		<PackageReference Include="Umbraco.Cms.StaticAssets" Version="15.4.2" />
 		<PackageReference Include="uSync" Version="15.1.5" />
 	</ItemGroup>