Bump the dotnet group with 1 update (#49365)

Bumps Microsoft.NET.Test.Sdk from 17.14.1 to 18.0.0

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

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

docs/azure/sdk/snippets/unit-testing/UnitTestingSampleApp.csproj

@@ -12,7 +12,7 @@
   <ItemGroup>
     <PackageReference Include="Azure.Core" Version="1.49.0" />
     <PackageReference Include="Azure.Security.KeyVault.Secrets" Version="4.8.0" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.14.1" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.0.0" />
     <PackageReference Include="Moq" Version="[4.20.72]" /> <!-- Context: https://github.com/Azure/azure-sdk-for-net/issues/38111 -->
     <PackageReference Include="NSubstitute" Version="5.3.0" />
     <PackageReference Include="xunit" Version="2.9.3" />