Update RedTeam target type visibility (#35447)

Author: posaninagendra

specification/ai/Azure.AI.Projects/red-teams/models.tsp

@@ -113,7 +113,6 @@ union RiskCategory {
 @added(Versions.v2025_05_15_preview)
 @removed(Versions.v1)
 model AzureOpenAIModelConfiguration extends TargetConfig {
-  @visibility(Lifecycle.Read)
   type: "AzureOpenAIModel";
 
   @doc("Deployment name for AOAI model. Example: gpt-4o if in AIServices or connection based `connection_name/deployment_name` (i.e. `my-aoai-connection/gpt-4o`.")