Increase timeout

Author: stevebux

tests/helpers/poll-for-letters-helper.ts

@@ -12,7 +12,7 @@ export async function pollForLetterStatus(
   const headers = createValidRequestHeaders(supplierId);
   let statusCode = 0;
   let letterStatus: string | undefined;
-  const RETRY_DELAY_MS = 10_000;
+  const RETRY_DELAY_MS = 20_000;
   const MAX_ATTEMPTS = 6;
 
   for (let attempt = 1; attempt <= MAX_ATTEMPTS; attempt++) {