[deps]: Update Microsoft.NET.Test.Sdk to v18

Author: renovate[bot]

test/Server.IntegrationTest/Server.IntegrationTest.csproj

@@ -10,7 +10,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.11.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.3.0" />
     <PackageReference Include="xunit.v3" Version="3.0.1" />
     <PackageReference Include="xunit.runner.visualstudio" Version="3.1.4" />
     <PackageReference Include="Microsoft.AspNetCore.Mvc.Testing" Version="8.0.10" />