Update packages-exp/auth-exp/test/integration/webdriver/util/test_runner.ts

Co-authored-by: Yuchen Shi <[email protected]>

Author: sam-gc

packages-exp/auth-exp/test/integration/webdriver/util/test_runner.ts

@@ -45,7 +45,7 @@ const SUITES: TempSuite[] = [];
 /** Main entry point for all WebDriver tests */
 export function browserDescribe(
   title: string,
-  generator: (driver: AuthDriver, browser?: string) => void
+  generator: (driver: AuthDriver, browser: string) => void
 ): void {
   SUITES.push({
     title,