(chore): upgrade versions to latest

Author: fern-api[bot]

fern/apis/api/generators.yml

@@ -81,7 +81,7 @@ groups:
   csharp-sdk:
     generators:
       - name: fernapi/fern-csharp-sdk
-        version: 1.9.5
+        version: 1.9.8
         github:
           repository: VapiAI/server-sdk-csharp
         output: