chore(internal): add type (#737)

Author: stainless-bot

src/streaming.ts

@@ -201,7 +201,7 @@ export class Stream<Item> implements AsyncIterable<Item> {
       async start() {
         iter = self[Symbol.asyncIterator]();
       },
-      async pull(ctrl) {
+      async pull(ctrl: any) {
         try {
           const { value, done } = await iter.next();
           if (done) return ctrl.close();