`QuotedTweet.self_thread` is optional in syndication responses

[ocavue]

react-tweet@3.3.1 requires QuotedTweet.self_thread to exist based on the type in tweet.ts.

However, the actual HTTP response doesn't have self_thread, as shown in the example below:

$ curl -fsSL https://react-tweet.vercel.app/api/tweet/1523695856074969088 | jq '.data.quoted_tweet.text'
"“It’s full of stars!” ✨\n\nThis mosaic represents a sparkling turning point as we #UnfoldTheUniverse. #NASAWebb’s mirrors are now fully aligned! Next is instrument calibration, the final phase before Webb is ready for science: https://t.co/PcAxajyMfI\n\nWhat do we see here? ⤵️ https://t.co/qzdZRbsgRF"

$ curl -fsSL https://react-tweet.vercel.app/api/tweet/1523695856074969088 | jq '.data.quoted_tweet.self_thread'
null