test: Fix flaky comments.list ordering assertion (#12329)

Two comments built back-to-back could share a millisecond-precision
createdAt, leaving the DESC-ordered result non-deterministic. Pass
explicit createdAt values so the assertion on body.data[1] is stable.

server/routes/api/comments/comments.test.ts

@@ -187,10 +187,12 @@ describe("#comments.list", () => {
     const comment = await buildComment({
       userId: user.id,
       documentId: document.id,
+      createdAt: new Date(Date.now() - 1000),
     });
     await buildResolvedComment(user, {
       userId: user.id,
       documentId: document.id,
+      createdAt: new Date(),
     });
     const res = await server.post("/api/comments.list", {
       body: {