Bump Microsoft.Extensions.AI from 9.7.0 to 9.8.0

---
updated-dependencies:
- dependency-name: Microsoft.Extensions.AI
  dependency-version: 9.8.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

sample/Cnblogs.DashScope.Sample/Cnblogs.DashScope.Sample.csproj

@@ -23,7 +23,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.Extensions.AI" Version="9.7.0" />
+    <PackageReference Include="Microsoft.Extensions.AI" Version="9.8.0" />
   </ItemGroup>
 
 </Project>