test: increase timeout for desktop issue transfer test (#117)

The "should transfer new frontend issue" test was timing out after the default 5 seconds
due to async streaming operations with pageFlow. Increased timeout to 20 seconds to match
other similar tests in the same file.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude <noreply@anthropic.com>

Author: snomiao

app/tasks/gh-issue-transfer-desktop-to-frontend/index.spec.ts

@@ -166,7 +166,7 @@ describe("GithubDesktopIssueTransferTask", () => {
     const lastOp = dbOperations[dbOperations.length - 1];
     expect(lastOp.data.sourceIssueNumber).toBe(123);
     expect(lastOp.data.commentPosted).toBe(true);
-  });
+  }, 20000);
 
   it("should skip pull requests", async () => {
     const pullRequest = {