fix(ci): remove stale agent_state config from responses provider in auth workflow

The upstream merge removed agent_state from ResponsesPersistenceConfig
but the CI workflow config still referenced it, causing Pydantic validation
to reject the provider config during initialization. This prevented the
responses table from being created, resulting in "no such table: responses"
OperationalError for all response access control tests.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Signed-off-by: Francisco Javier Arceo <farceo@redhat.com>

Author: franciscojavierarceo

.github/workflows/integration-responses-conversations-auth-tests.yml

@@ -144,9 +144,6 @@ jobs:
                 provider_type: inline::builtin
                 config:
                   persistence:
-                    agent_state:
-                      namespace: responses
-                      backend: kv_default
                     responses:
                       table_name: responses
                       backend: sql_default