(chore): upgrade versions to latest (#116)

Co-authored-by: fern-api[bot] <115122769+fern-api[bot]@users.noreply.github.com>

Author: fern-api[bot]

fern/apis/api/generators.yml

@@ -47,7 +47,7 @@ groups:
   java-sdk:
     generators:
       - name: fernapi/fern-java-sdk
-        version: 2.3.1
+        version: 2.8.1
         output:
           location: maven
           coordinate: dev.vapi:server-sdk