Bump System.Text.Json from 9.0.0 to 9.0.2 in /build (#346)

Bumps [System.Text.Json](https://github.com/dotnet/runtime) from 9.0.0 to 9.0.2.
- [Release notes](https://github.com/dotnet/runtime/releases)
- [Commits](dotnet/runtime@v9.0.0...v9.0.2)

---
updated-dependencies:
- dependency-name: System.Text.Json
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Robert Coltheart <13191652+robertcoltheart@users.noreply.github.com>

Author: dependabot[bot]

build/build.csproj

@@ -9,7 +9,7 @@
     <PackageReference Include="Bullseye" Version="4.2.1" />
     <PackageReference Include="Glob" Version="1.1.9" />
     <PackageReference Include="SimpleExec" Version="11.0.0" />
-    <PackageReference Include="System.Text.Json" Version="9.0.0" />
+    <PackageReference Include="System.Text.Json" Version="9.0.2" />
   </ItemGroup>
 
 </Project>