simplify code

Author: chargome

packages/nextjs/src/common/nextNavigationErrorUtils.ts

@@ -7,9 +7,9 @@ import { isError } from '@sentry/utils';
 export function isNotFoundNavigationError(subject: unknown): boolean {
   return (
     isError(subject) &&
-    ((subject as Error & { digest?: unknown }).digest === 'NEXT_NOT_FOUND' ||
-      // this was introduced in 15.0.4-canary.18: https://github.com/vercel/next.js/pull/72774
-      (subject as Error & { digest?: unknown }).digest === 'NEXT_HTTP_ERROR_FALLBACK;404')
+    ['NEXT_NOT_FOUND', 'NEXT_HTTP_ERROR_FALLBACK;404'].includes(
+      (subject as Error & { digest?: unknown }).digest as string,
+    )
   );
 }