It's not liking the double quotations. Those are the curly double quotations. Can you try this again with the double quotations replaced with the straight double quotations, such as below. You can do it by hand or you can use the ` symbol before and after the command here in slack and it'll replace it for you, like so:
gcloud iam roles create arizeApp --project=ai-project-id --title="Arize App" --description="Custom IAM role for Arize App" --permissions=aiplatform.endpoints.predict --stage=ALPHA