🐛(frontend) fix flaky test

Depend the month the test could fail if the current
month has 30 or 31 days, so change 30 to 35 to be sure
that it will always be at least 1 month ago.

src/frontend/apps/impress/src/features/docs/docs-grid/components/__tests__/DocsGridItemDate.test.tsx

@@ -44,7 +44,7 @@ describe('DocsGridItemDate', () => {
       rendered: '5 days ago',
     },
     {
-      updated_at: DateTime.now().minus({ days: 30 }).toISO(),
+      updated_at: DateTime.now().minus({ days: 35 }).toISO(),
       rendered: '1 month ago',
     },
   ].forEach(({ updated_at, rendered }) => {