Bump System.Text.Json from 6.0.10 to 9.0.10

---
updated-dependencies:
- dependency-name: System.Text.Json
  dependency-version: 9.0.10
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

AiHelpBot/AiHelpBot.csproj

@@ -19,7 +19,7 @@
     </ItemGroup>
 
     <ItemGroup>
-      <PackageReference Include="System.Text.Json" Version="6.0.10" />
+      <PackageReference Include="System.Text.Json" Version="9.0.10" />
       <None Update="SystemPrompt.txt">
         <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
       </None>