build(deps): bump System.Text.Json from 7.0.3 to 8.0.4 in /ShopifySharp

Bumps System.Text.Json from 7.0.3 to 8.0.4.

---
updated-dependencies:
- dependency-name: System.Text.Json
  dependency-type: direct:production
...

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

ShopifySharp/ShopifySharp.csproj

@@ -23,6 +23,6 @@
     <PackageReference Include="Microsoft.Extensions.Http" Version="2.1.0" />
     <PackageReference Include="Microsoft.SourceLink.GitHub" Version="1.1.1" PrivateAssets="all" />
     <PackageReference Include="newtonsoft.json" Version="13.0.2" />
-    <PackageReference Include="System.Text.Json" Version="7.0.3" />
+    <PackageReference Include="System.Text.Json" Version="8.0.4" />
   </ItemGroup>
 </Project>