chore: bumps STJ version for tests project

Author: baywet

test/Microsoft.OpenApi.Tests/Microsoft.OpenApi.Tests.csproj

@@ -13,7 +13,7 @@
     <PackageReference Include="FluentAssertions" Version="7.2.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.14.1" />
     <PackageReference Include="Moq" Version="4.20.72" />
-    <PackageReference Include="System.Text.Json" Version="9.0.6" />
+    <PackageReference Include="System.Text.Json" Version="9.0.7" />
     <PackageReference Include="Verify.Xunit" Version="30.4.0" />
     <PackageReference Include="xunit" Version="2.9.3" />
     <PackageReference Include="xunit.runner.visualstudio" Version="3.1.1" PrivateAssets="all" />