Bump Microsoft.NET.Test.Sdk from 17.14.1 to 18.0.0 (#128)

---
updated-dependencies:
- dependency-name: Microsoft.NET.Test.Sdk
  dependency-version: 18.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Robert Andersson <inputfalken@gmail.com>

Author: dependabot[bot]

tests/DynamoDBGenerator.SourceGenerator.Tests/DynamoDBGenerator.SourceGenerator.Tests.csproj

@@ -12,7 +12,7 @@
     <ItemGroup>
         <PackageReference Include="AutoFixture" Version="5.0.0-preview0012" />
         <PackageReference Include="FluentAssertions" Version="7.0.0"/>
-        <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.14.1" />
+        <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.0.0" />
         <PackageReference Include="xunit.runner.visualstudio" Version="3.1.5">
           <PrivateAssets>all</PrivateAssets>
           <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>