Upgrade React from `2bcbf254-20251020` to `71b3a03c-20251021`#85177

nextjs-bot wants to merge 6 commits intocanaryvercel/next.js:canaryfrom

update/react/19.3.0-canary-71b3a03c-20251021vercel/next.js:update/react/19.3.0-canary-71b3a03c-20251021Copy head branch name to clipboard