Bump Microsoft.NET.Test.Sdk from 17.12.0 to 18.3.0

---
updated-dependencies:
- dependency-name: Microsoft.NET.Test.Sdk
  dependency-version: 18.3.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

tests/ShedBuilder.Api.Tests/ShedBuilder.Api.Tests.csproj

@@ -12,7 +12,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.AspNetCore.Mvc.Testing" Version="8.0.11" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.InMemory" Version="8.0.11" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.3.0" />
     <PackageReference Include="Moq" Version="4.20.72" />
     <PackageReference Include="xunit" Version="2.9.3" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2">